Greek trade unions have begun the first general strike since the country’s conservative-led coalition government came to power in June.
Wednesday’s 24-hour walkout is to protest at new planned spending cuts of more than 11.5 billion euros ($15 billion).
The savings are a pre-condition to Greece receiving its next tranche of bailout funds, without which the country could face bankruptcy in weeks.
Large anti-austerity demonstrations are also planned.
Greek trade unions have begun the first general strike since the country’s conservative-led coalition government came to power in June
Greece needs the next 31 billion-euro installment of its international bailout, but with record unemployment and a third of Greeks pushed below the poverty line, there is strong resistance to further cuts.
The government of conservative Prime Minister Antonis Samaras is also proposing to slash pensions and raise the retirement age to 67.
Workers from a diverse range of sectors are taking part in the strike, from doctors to air traffic controllers.
It was called by the country’s two biggest unions, which between them represent half the workforce.
A survey conducted by the MRB polling agency last week found that more than 90% of Greeks believed the planned cuts were unfair and a burden on the poor.
With demonstrations planned, many people fear a repeat of the violence that has hit the streets in previous protests.
Thousands of police have been deployed in the centre of Athens to prevent a flare-up.
Greece is currently trying to qualify for the next installment of its 130 billion-euro bailout, which is backed by the IMF and the other 16 euro nations.
The country was given a 110 billion-euro package in May 2010 and a further 130 billion euros in October 2011. That money is paid in installments, but correspondents say the donors are reluctant to stump up the latest slice, as they feel Greece has not made enough effort to meet its deficit-reduction targets.
Greece needs the next tranche of its bailout to make repayments on its debt burden. A default could result in the country leaving the euro.
Trade unions in Nigeria have announced an indefinite strike and mass demonstrations unless the removal of a fuel subsidy is reversed.
The fuel subsidy’s withdrawal has led petrol prices to more than double since Monday, prompting anger countrywide.
“We have the total backing of all Nigerian workers on this strike and mass protest,” said the Nigeria Labour Congress’s Chris Uyot.
Nigeria is Africa’s biggest oil producer, but imports refined petrol.
Both the NLC and the Trades Union Congress (TUC) have agreed to the strike.
NLC spokesman Chris Uyot told the BBC’s Focus on Africa programme there was no room for dialogue with the government, which has said it will spend the money saved by removing the subsidy on improving the country’s erratic electricity supply, as well as on health and education.
Trade unions in Nigeria have announced an indefinite strike and mass demonstrations unless the removal of a fuel subsidy is reversed
Prices have increased from 65 naira ($0.40) per litre to at least 140 naira in filling stations and from 100 naira to at least 200 on the black market, where many Nigerians buy their fuel.
“After exhaustive deliberations and consultations with all sections of the populace, the NLC, TUC and their pro-people allies demand that the presidency immediately reverses fuel prices to 65 naira,” a statement signed by the heads of the two unions said.
If the government failed to do so, “all offices, oil production centres, air and sea ports, fuel stations, markets, banks, amongst others will be shut down” from Monday 9 January, the statement said.
“We advise Nigerians to stockpile basic needs especially food and water,” the statement added.
There has been a furious reaction this week to the fuel price increase – one protester was killed on Tuesday in Irolin, Kwara state, and thousands of Nigerians have demonstrated in cities across the country.
Nigeria’s Central Bank Governor Lamido Sanusi said the subsidy – which he said cost the government about $8 billion last year – was “unsustainable”.
“Subsides should be for production and not consumption,” he told Focus on Africa.
In December, the Nigerian government released a list of the people who benefit most from the subsidy, which include some of Nigeria’s richest people – the owners of fuel-importing firms.
Years of mismanagement and corruption mean Nigeria does not have the capacity to refine oil into petrol and other fuels.
Several previous governments have tried to remove the subsidy but have backed down in the face of widespread public protests and reduced it instead.
The IMF has long urged Nigeria’s government to remove the subsidy.