According to US officials, North Korea has tested a new rocket engine as part of its efforts to build a missile capable of reaching the US mainland.
The news comes amid rising tensions between Washington and Pyongyang over North Korea’s nuclear ambitions.
The Trump administration has made the issue one of its top priorities.
Despite international condemnation, North Korea has increased its missile tests, with the aim of developing an intercontinental nuclear-armed rocket.
Last month, the US Defense Intelligence Agency warned that North Korea was on an “inevitable” path to achieving this.
On June 22, US officials speaking anonymously to several news agencies said the latest engine test could be one stage of an intercontinental ballistic missile (ICBM) engine that would be able to reach the American mainland.
Due to the secretive nature of all of North Korea’s military activity, it is hard for experts to assess how close the country is to building a reliable ICBM.
On June 21, Secretary of State Rex Tillerson urged China to use more diplomatic pressure on North Korea “if they want to prevent further escalation in the region”.
China is seen as North Korea’s main ally and the US hopes Beijing can have greater influence on the totalitarian state to stop both its missile tests and nuclear program.
President Donald Trump has said he would like to solve the North Korea crisis diplomatically, but has previously warned that a “major, major conflict” is possible.
Tensions spiked once again last week when American student Otto Warmbier, who was serving a hard labor sentence in North Korea for stealing a propaganda sign, died shortly after returning home in a coma.
The US has also ramped up its military presence in the region, conducting drills with Japan as well as South Korea, and is installing a controversial missile defense system in South Korea, known as Terminal High-Altitude Area Defense system (THAAD).
However, South Korea recently said it was suspending the further deployment of the system until an environmental assessment was completed.