“There is a hollow space, which measures about 60 to 100 metres in length, at the bottom of Mount Mantap in the Punggye-ri site,” Nam Jae-cheol was quoted by South Korean news agency Yonhap as saying.
“Should another nuke test occur, there is the possibility of a collapse,” he warned.
The Punggye-ri test site, situated in mountainous terrain in the north-east of North Korea, is thought to be Pyongyang’s main nuclear facility and the only active nuclear testing site in the world.
Hong Kong’s South China Morning Post newspaper reported on October 27 that Chinese geologists warned North Korean officials after the September test that additional tests there could lead to a massive collapse and a leak of radioactive waste.
Meanwhile, North Korea’s main newspaper, Rodong Sinmun, has said the country has a sovereign right to launch satellites.
The statement comes amid speculation that North Korea might soon launch a satellite – widely seen as a test of the country’s ballistic missile technology.
Meanwhile, South Korea’s navy carried out live-fire naval drills on September 5, warning that if North Korea provoked them “we will immediately hit back and bury them at sea”, reported Yonhap news agency.
It comes a day after South Korea’s military simulated a missile attack on North Korea’s nuclear test site.
Reports suggest North Korea is preparing new test missile launches.
On September 3, North Korea tested a bomb underground, which was thought to have a power range from 50 kilotonnes to 120 kilotonnes. A 50kt device would be about three times the size of the bomb that destroyed Hiroshima in 1945.
Nikki Haley argued that only the strongest sanctions would enable the problem to be resolved through diplomacy.
“War is never something the United States wants,” she said.
“We don’t want it now but our country’s patience is not unlimited.”
China Ambassador to the UN Liu Jieyi reiterated a call for all sides to return to negotiations.
“The peninsula issue must be resolved peacefully,” he said.
“China will never allow chaos and war on the peninsula.”
North Korea has conducted a ballistic test in for the first time since President Donald Trump took office.
President Trump assured Japan’s PM Shinzo Abe that “America stands behind Japan, its great ally, 100%”.
The ballistic missile fired by North Korea flew east towards the Sea of Japan for about 310 miles, South Korean officials say.
PM Shinzo Abe said the test was “absolutely intolerable”. According to Japanese officials, the missile did not reach its waters.
Speaking at a joint press conference during a visit to the US, Shinzo Abe added that Donald Trump had also assured him that he was committed to “further enforcing our alliance”.
North Korea has conducted a number of nuclear tests in the past year in acts of aggression that continue to alarm and anger the region.
Image source Reuters
February 12 launch took place at 07:55 local time from the Banghyon air base in North Pyongan province on the west side of the Korean peninsula.
The missile reached an altitude of about 350 miles, according to a South Korean official quoted by Reuters, and appeared to be a Rodong medium-range missile.
South Korea’s foreign ministry said: “North Korea’s repeated provocations show the Kim Jong-un regime’s nature of irrationality, maniacally obsessed in its nuclear and missile development.”
Japan’s Chief Cabinet Secretary Yoshihide Suga confirmed the missile had not reached Japanese territorial waters, adding that Tokyo would make a “strong protest” to North Korea over the incident.
There has so far been no comment from North Korea.
Kim Jong-un said last month that North Korea was close to testing long-range missiles capable of carrying nuclear warheads.
On a visit to South Korea last week, Defense Secretary James Mattis said that any use of nuclear weapons by North Korea would be met with an “effective and overwhelming” response.
James Mattis also reconfirmed plans to deploy a US missile defense system in South Korea later this year.
North Korea conducted its fifth test of a nuclear device in 2016, and claims it is capable of carrying out a nuclear attack on the US, though experts are still unconvinced that its technology has progressed that far.
North Korea has also said in recent weeks that it has a new intercontinental ballistic missile, capable of reaching the US mainland, which it is prepared to test launch at any time.
According to South Korean officials, North Korea could be ready to conduct another nuclear test at any time.
North Korea conducted its fifth underground nuclear test on September 9, thought to be its most powerful yet.
A South Korean defense ministry spokesman said there was still an unused tunnel at the Punggye-ri test site which could be used for a sixth explosion at any time.
Last week’s widely condemned test has ratcheted up tension and led to fierce rhetoric from South Korea.
On September 11, one South Korean military source told the Yonhap news agency that Pyongyang could be annihilated if it showed any signs of mounting a nuclear attack.
While doubts remain over North Korea’s claim that it can now mount nuclear warheads on ballistic rockets – meaning it can carry out a nuclear attack – experts say the recent progress is worrying.
On September 12, Yonhap cited an unnamed government source as saying reports indicated the North had finished preparations for a further test, in previously unused tunnel at the Punggye-ri site deep underneath mountains in the north-east.
“Intelligence authorities in Seoul and Washington are keeping close tabs,” the unnamed government official was quoted as saying.
Defense ministry spokesperson Moon Sang-gyun later gave a similar statement to reporters. He would not give further details citing security reasons.
The UN Security Council has already agreed to start drawing up new sanctions against North Korea, something the North called “laughable”.
Pyongyang has carried out two nuclear tests in 2016, as well as several tests of powerful missiles. Both are banned by existing sanctions.
On September 12, Japan’s Kyodo news agency reported that North Korean Foreign Minister Ri Yong-ho had arrived in Beijing.
China is North Korea’s main ally and trading partner, but has grown increasingly intolerant of its military actions and Kim Jong-un’s aggressive rhetoric.
China’s support for toughened sanctions is crucial if they are to have any impact.
President Barack Obama has rejected North Korea’s proposal to halt nuclear tests if the US ceases its annual military exercises with South Korea.
On April 24, Barack Obama told reporters that the US did not take such a proposal seriously and that Pyongyang would “have to do better than that”.
North Korean foreign minister Ri Su-yong made the offer in a rare interview.
Annual military drills conducted by the US and South Korea routinely inflames tensions with North Korea.
Ri Su-yong’s comments came as North Korea said it fired a ballistic missile from a submarine off its eastern coast.
The UN condemned the test, which it called a “serious violation” of past resolutions aimed at curbing North Korea’s nuclear ambitions.
International sanctions have been stepped up in the wake of several controversial nuclear and missile tests by North Korea.
The latest allegedly took place last week, with North Korea claiming to have used “cold launch” technology to fire a missile from a submarine, where it is expelled using gas pressure.
North Korea also conducted its fourth nuclear test with a hydrogen bomb in January sparking worldwide condemnation, and claimed last month that it has developed nuclear warheads small enough to fit on ballistic missiles, though experts have disputed such claims.
Analysts believe that North Korea may be gearing up for a fifth nuclear test as a show of strength ahead of the Workers’ Party Congress, the first since 1980.
North Korean Foreign Minister Ri Su-yong has said his country will suspend its nuclear tests if the US stops its annual military exercises with South Korea.
Ri Su-yong also told the Associated Press that his country would not be cowed by international sanctions.
A US official has defended the drills as a sign of commitment to South Korea.
Meanwhile, Pyongyang said April 23 submarine-launched ballistic missile test was a “great success”.
“It fully confirmed and reinforced the reliability of the Korean-style underwater launching system and perfectly met all technical requirements for carrying out… underwater attack operation,” the North Korean news agency KCNA said.
The report added that the test gave North Korea “one more means for powerful nuclear attack”.
North Korea is banned from nuclear tests and activities that use ballistic missile technology under UN sanctions dating back to 2006.
Earlier, Ri Su-yong defended North Korea’s right to have a nuclear deterrent and said the US drove North Korea to develop such weapons as an act of self-defense.
The minister said that the suspension of the military drills could open the door to talks and reduced tensions.
“If we continue on this path of confrontation, this will lead to very catastrophic results, not only for the two countries but for the whole entire world as well,” he told AP.
“Stop the nuclear war exercises in the Korean Peninsula, then we should also cease our nuclear tests.”
It was a rare interview by a top North Korean official with a foreign media outlet. The conversation took place in North Korea’s diplomatic mission at the UN, AP said.
An unnamed US official quoted by AP defended the drills in South Korea as demonstrating Washington’s commitment to its alliance with Seoul.
The US has insisted North Korea give up its nuclear weapons program first before any negotiations and has ignored similar proposals in the past, according to the agency.
Ri Su-yong also said sanctions would not sway his country: “If they believe they can actually frustrate us with sanctions, they are totally mistaken.
“The more pressure you put on to something, the more emotionally you react to stand up against it. And this is important for the American policymakers to be aware of.”
The interview came hours after North Korea said it launched a ballistic missile from a submarine, a type of missile hard to detect.
The United States and China say a new UN resolution against North Korea is needed, following Pyongyang’s claim that it had successfully tested a hydrogen bomb earlier this month.
Secretary of State John Kerry, who is in Beijing for talks, called North Korea’s nuclear ambitions a “threat to the world” and urged new sanctions.
However, his Chinese counterpart Wang Yi suggested China would not support any sanctions.
China is North Korea’s main ally, but has condemned Pyongyang’s nuclear test.
On January 6, a 5.1 magnitude tremor was detected in North Korea – which said it had successfully conducted an underground hydrogen bomb test.
However, nuclear experts questioned North Korea’s claim, saying the size of the blast was not large enough to have been from an H-bomb.
Speaking on January 27 after talks with Wang Yi, John Kerry said that both sides agreed on the need for a “strong” resolution against North Korea, and said that limiting the trade of goods and services across China’s border with North Korea was one potential measure.
However, Wang Yi said that while China supported the need for a new resolution, it “should not provoke new tension in the situation, still less destabilize the Korean peninsula”.
“Sanctions are not an end in themselves,” he added.
China is Pyongyang’s biggest trading partner, and major ally – although relations have cooled since Kim Jong-un succeeded his father.
Nonetheless, experts say China is wary of destabilizing North Korea, fearing that millions of North Korean refugees could pour across China’s borders if the regime collapsed.
The two sides also discussed the disputed South China Sea, where China has multiple competing territorial claims with other countries.
China has angered several neighbors by constructing artificial islands on claimed reefs, and building runways and other facilities on them.
John Kerry called on China to stop construction and land reclamation in disputed areas.
However, Beijing said such activity was within its legal rights to protect its territorial sovereignty.
John Kerry, who will also meet China’s State Councilor Yang Jiechi and President Xi Jinping, is on an Asia tour that has included Laos and Cambodia.
South Korea, Japan and the United States have said they will be united in their response to North Korea’s claim to have successfully tested a hydrogen bomb.
North Korea said it carried out the test on January 6.
If confirmed it would be North Korea’s fourth nuclear test, and its first of the more powerful H-bomb.
The UN Security Council has also agreed to start drawing up new measures against North Korea.
However, skepticism remains over whether North Korea really did conduct such a test.
Experts have said the seismic activity generated by the blast was not large enough for it to have been a full thermonuclear explosion.
The White House said President Barack Obama had spoken separately to South Korea’s President Park Geun-Hye and Japan’s PM Shinzo Abe.
They “agreed to work together to forge a united and strong international response to North Korea’s latest reckless behavior”, it said in a statement.
PM Shinzo Abe told reporters: “We agreed that the provocative act by North Korea is unacceptable… We will deal with this situation in a firm manner through the cooperation with the United Nations Security Council.”
He added that Japan may take unilateral action, saying it is “considering measures unique to our nation”.
South Korea’s presidential office said in a statement that Presidents Geun-hye and Barack Obama had agreed to closely co-operate and that the international community “must make sure that North Korea pays the corresponding price” for the nuclear test, reported Yonhap news agency.
The UN Security Council held an emergency session on January 6 and condemned the test claim as “a clear threat to international peace and security.”
Japan’s ambassador to the UN, Motohide Yoshikawa, called for a swift and robust new UN resolution, insisting: “The authority and credibility of the Security Council will be put in question if it does not take these measures.”
However, the UN ambassador for Russia, which has been developing warmer relations with Pyongyang, said it would be going “too far” to say Moscow supported further sanctions.
Meanwhile, South Korea has begun limiting entry to the Kaesong industrial park in North Korea, jointly run by both countries. Only those directly involved in operations there will be allowed to enter from the South, said Seoul’s Unification Ministry.
South Korea has also said it will restart propaganda broadcasts across the border on January 8, an act which North Korea strongly opposes. The broadcasts were stopped in 2015 as part of a deal with North Korea to ease tensions that had escalated sharply in the summer.
The nuclear test came days before North Korean leader Kim Jong-un’s 33rd birthday, which falls on January 8 and is expected to be marked by celebrations.
Hydrogen bombs are more powerful and technologically advanced than atomic weapons, using fusion – the merging of atoms – to unleash massive amounts of energy.
Atomic bombs, like those that devastated two Japanese cities in World War Two, use fission, or the splitting of atoms.
South Korea’s intelligence agency also told politicians that the estimated power of the blast fell far short of what would be expected from a hydrogen bomb.
Some analysts have suggested it is possible Pyongyang tested a “boosted” atomic bomb, which uses some fusion fuel to increase the yield of the fission reaction.
The United States and nearby countries are thought to be carrying out atmospheric sampling, hoping to find leaked radioactive material, which would give clues as to what kind of device was tested.
The UN Security Council has announced it will begin work immediately on new measures against North Korea, after Pyongyang claimed it had tested a hydrogen bomb.
The council condemned the test, saying “a clear threat to international peace and security continues to exist”.
This is North Korea’s fourth nuclear test since 2006, but if confirmed would be the first of an H-bomb.
However, the US has joined nuclear experts in questioning whether the blast was large enough for such a test.
White House spokesman Josh Earnest said “initial analysis was not consistent with North Korea’s claims of a successful hydrogen bomb test”.
Josh Earnest added: “Nothing that has occurred in the last 24 hours has caused the United States government to change our assessment of North Korea’s technical and military capabilities.”
The Security Council held an emergency session on January 6. It was called by the US, Japan and South Korea.
Uruguay’s UN Ambassador Elbio Rosselli, current president of the council, said: “The members… recalled that they have previously expressed their determination to take further significant measures in the event of another [North Korea] nuclear test.
“In line with this commitment and the gravity of this violation, [they] will begin to work immediately on such measures in a new Security Council resolution.”
Josh Earnest said North Korea’s isolation had “deepened as they have sought to engage in increasingly provocative acts”.
Japan’s ambassador to the UN, Motohide Yoshikawa, called for a swift and robust new UN resolution.
Motohide Yoshikawa said: “The authority and credibility of the Security Council will be put in question if it does not take these measures.”
However, Motohide Yoshikawa and other members have not spelled out what they will be or when the resolution could be adopted.
Russia’s UN ambassador said it would be going “too far” to say Moscow supported further sanctions.
North Korea’s tests in 2006, 2009 and 2013 triggered UN sanctions, with 20 entities and 12 individuals on a UN blacklist.
If an H-bomb test were confirmed, it would mark a major upgrade in North Korea’s nuclear capabilities.
Hydrogen bombs are more powerful and technologically advanced than atomic weapons, using fusion – the merging of atoms – to unleash massive amounts of energy.
Atomic bombs, like the kind that devastated two Japanese cities in World War Two, use fission, or the splitting of atoms.
A South Korean politician, Lee Cheol-woo, said he was briefed by the country’s intelligence agency that the blast “probably falls short” of a hydrogen detonation.
Suspicions that North Korea had carried out a nuclear test were raised when an earthquake was registered near the Punggye-ri nuclear site in North Korea at 10:00 Pyongyang time, with the tremors rattling Chinese border cities.
Hours later, in a surprise announcement, a newsreader on North Korean state TV said: “The republic’s first hydrogen bomb test has been successfully performed at 10:00 am on January 6, 2016.”
A note signed by North Korea leader Kim Jong-un authorizing the test said 2016 should begin with the “stirring explosive sound” of a hydrogen bomb.
China and Japan are reported to have been trying to detect radiation.