Fuel prices in Nigeria have more than doubled a day after the oil-rich nation ended a popular consumer fuel subsidy.

Prices at the pump on Monday soared from about 40 cents to 88 cents per liter.

The Nigerian government ended the subsidy program on Sunday. President Goodluck Jonathan has said the money used on the $7.5 billion program would be better spent on infrastructure and social programs.

However, the Nigeria Labor Congress and the Trade Union Congress said in a joint statement Monday that the subsidy elimination is “callous and insensitive.”

The unions said in coming days they will call for nationwide strikes, demonstrations and mass protests.

The fuel subsidy was one of the few benefits of Nigeria's oil wealth enjoyed by the average person.

Militants in oil-rich southern Nigeria attacked government and oil industry targets for years, demanding that more oil revenue be spent on impoverished communities in the region.

The attacks largely stopped after a government amnesty in 2009, but oil firms still battle tapping and sabotage of their pipelines.

Some lawmakers in the House of Representatives have said they will fight to bring back the fuel subsidy.