There was no immediate impact on the flow of oil from this volatile West African nation, which is Africa's largest oil producer and the fifth-biggest source of U.S. oil imports.
Union militants smashed car windows to keep people home in Lagos, and the streets were nearly empty of traffic except for soldiers and anti-riot police in armored vehicles. Banks, stores and schools remained shuttered.
"The strike is on. Nigerians are united over this," said Owei Lakemfa, a spokesman for Nigeria Labor Congress, an umbrella group of 29 unions.
There was only partial compliance with the strike call in Abuja, the capital, and some other cities, where many shops opened and taxis cruised the streets. But businesses and schools did not open in the northern city of Kaduna, and protesters burned tires in the streets.
Crude for November delivery traded at $53.70 a barrel Monday afternoon, up 39 cents from Friday's record settlement price of $53.31 on the New York Mercantile Exchange. Prices had pushed as high as $53.80.
While traders expressed concern over possible supply shortages from Nigeria, information minister Chukwuemeka Chikelu and executives at multinational oil companies said the strike had not hurt Nigeria's daily output of 2.5 million barrels.
"Our people are working. There's been no impact," said Udom Inoyo at Mobil Producing Nigeria Unlimited, a subsidiary of ExxonMobil, the second biggest oil producer in Nigeria.
Royal Dutch/Shell, which accounts for roughly half of Nigeria's oil exports, said its executive offices in Lagos were mostly empty but its "oil production and exports are going ahead."
Union leaders demanded a rollback in last month's jump in the price of gasoline to about $1.50 a gallon from $1.19, the latest in a series of increases from a government push to cut subsidies and deregulate the economy. The hikes set off widespread protests.
A coalition of civic groups and opposition parties, including the main opposition All Nigerian People's Party, expressed support for the strike.
Weekend negotiations failed to head off the strike. The chief of the National Labor Congress, Adams Oshiomhole, accused President Olusegun Obasanjo of shunning dialogue.
Obasanjo held more talks with Oshiomhole and other union leaders in Abuja on Monday trying to resolve the strike.
The president said a 33-member committee, composed of government ministers and officials as well as five union leaders, had been set up to "bring about short-term relief and medium-term positive impact on the effects of high oil prices." He gave no details.
The strike was the latest oil-related challenge to Obasanjo's government in just a few weeks. Late last month, a militant group declared "full-scale war" on the oil industry to press its demand that more of Nigeria's oil wealth be funneled to the poor of the oil-rich Niger Delta. The group withdrew its threat after reaching a deal with Obasanjo.
In Lagos, soldiers and police were out in force, patrolling in armored vehicles through the city's deserted central business district.
Union militants, too, were out in large numbers to enforce the strike.
On one major highway, an Associated Press reporter saw more than 500 protesters stop several vehicles, smash their windshields and order their drivers to turn back. The crowd was later dispersed by police who fired tear gas and shot their weapons in the air.
"The police are on top of the situation and people are going about their lawful business," Chris Olakpe, national police spokesman, told The Associated Press. "There's been no reason to make any arrests."
Leaders of two key oil worker unions were participating in the strike.
"It's going as planned," said Peter Akpatason, president of the blue-collar National Union of Petroleum and Natural Gas Workers of Nigeria. "Office workers are expected to stay at home and we're not allowing crew changes at production and export facilities."
Crews on the job at oil production and export facilities, however, were still working, Akpatason said.
The white-collar Petroleum and Natural Gas Senior Staff Association of Nigeria said its members would only strike on Monday. "We believe dialogue alone will resolve the problem," said Babatunde Oguns, the union's deputy president.
Union leaders said the walkout would end Friday, but warned that an indefinite general strike would be called if the government didn't reverse the price increases within two weeks.
A general strike in Nigeria last year shut down businesses in Lagos and several other cities for eight days, prompting a government crackdown during which police killed at least 11 protesters. Crude oil exports were unaffected.
___
Associated Press writer Daniel Balint-Kurti in Abuja contributed to this report.
