Ethnic violence has become widespread in recent weeks

The strike would come in the run-up to national elections in Africa's most populous country and could further disrupt the country's oil production.

Ongoing clashes between warring factions in the Niger Delta oilfields have already led to a 40% drop in Nigeria's oil output, leading to a rise in world oil prices.

With a daily production of some 2.1 million barrels a day, Nigeria is the world's sixth-biggest exporter.

The NLC union, which is pressing for the strike, is affiliated with the blue collar oil workers' union Nupeng.

The dispute is over the government's failure to implement a 12.5% salary increase agreed last year.

Elections

Nigerians are to go to the polls between 12 April and 3 May, but the elections have already been overshadowed with ongoing violence.

Nigerian President Olusegun Obasanjo faces a tough election battle on 19 April.

The Nigerian president has said a wage increase could deteriorate the West African country's dire economic problems, an argument rejected by the NLC.

The deputy president of the NLC, Joseph Akinlaja, played down concerns the strike could lead to a disruption of next month's elections.

"If we are conscious of that fact, the government should be conscious of it too," he said.

"We have written to them but up to now no meeting has been summoned. They are busy campaigning for elections."