Nigeria’s main trade union federation is pressing ahead with a general strike, despite a court injunction against the action.
The Nigeria Labour Congress (NLC) announced the strike after the government raised fuel prices by 67%.
It is not immediately clear how widely the strike is being observed. Public schools in Abuja remain open.
Banks, markets and many government offices are also open and there is heavy traffic on the capital’s roads.
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Another union grouping, the Trade Union Congress, earlier said it was suspending strike action by its members.
And it was unclear how many NLC members were joining the strike.
The BBC’s Chris Ewokor in Abuja said one NLC faction, which includes workers in the oil and gas sector, opposed the strike and was not planning to take part.
One member of that group, Joe Ajaero, told AFP news agency: “We have asked the government to cushion the effects of the price increase on the people as well as make petrol readily available.
“[The] government has to increase the minimum wage… because of the multiplier effects of the petrol price hike on foodstuffs, goods and services.”
The government called the strike “illegal” and said it would invoke the “no work, no pay” rule against any workers who joined the industrial action.
Officials said attendance of public sector workers would be monitored and security agents had been deployed to respond to any acts intended to deter employees from going to work, such as locking of offices or blocking of roads.
The National Industrial Court had ruled the strike should not go ahead because of the risk of civil disorder.
“The decision… is that strike continues tomorrow. We have reached a dead end,” NLC President Ayuba Wabba said on Tuesday after the union’s delegation walked out of a meeting with government officials.
The government called the decision by the NLC, which represents millions of workers, “regrettable”.
“Government, therefore, calls upon and advises all workers to respect the laws of the land and to desist from participating in an illegal strike action,” said spokesman David Babachir Lawal.
The court order followed an application by Justice Minister Abubakar Malami.
“It is the order of this court that [the] status quo be maintained,” Judge Babatunde Adejumo said in his ruling.
“The defendants are hereby restrained from carrying out the [strike] threat.”
The government announced last week that petrol prices would be increased in an attempt to ease fuel shortages.
Petroleum Minister Emmanuel Ibe Kachikwu said the move should stabilise the market.
The NLC branded the price rise “criminal” and called for it to be reversed.
In 2012, the government was forced to back down from a similar price rise after nationwide protests.
Despite being one of Africa’s largest oil producers, Nigeria has to import fuel to meet demand as its refineries are dilapidated and work at a fraction of their capacity.