A Nigerian militant group has announced a ceasefire and pledged to support talks with the government, after months of attacks on the country's oil and gas infrastructure that have crippled the economy.

In a message posted on the Niger Delta Avengers’ (NDA) website late on Saturday, the group said it would “observe a cessation of hostilities,” although not without conditions.

It said it would support efforts to negotiate with “the federal government of Nigeria, representatives from the home countries of all multinational oil corporations and neutral international mediators.”

There have been unconfirmed reports for several weeks of talks underway with Abuja, but the rebel group never publicly acknowledged that it was engaged in negotiations, or that it would support efforts by community figures from the area.

The NDA’s ceasefire announcement was not unconditional however, as the group said it would honour its pledge “unless the ruling political APC (All Progressives Congress party) continues ... to arrest, intimidate, invade and harass innocent citizens and invade especially Ijaw communities.”

The Ijaw ethnic people have long dominated oil rebel groups operating in the area, though experts say militants from other communities have also set up new branches.

“We promise to fight more for the Niger Delta, if this opportunity fails,” the NDA said.

The group has carried out a string of devastating attacks on Nigeria’s oil pipelines and facilities since the start of the year.

Two state-owned pipelines were blown up in the delta region on Friday, in attacks blamed on the NDA.

Also on Friday, a newly emerged group calling itself the Niger Delta Greenland Justice Mandate (NDGJM) claimed responsibility for an attack on the same day.

Earlier this month, the NDA threatened to pull the oil region out of Nigeria, accusing President Muhammadu Buhari of fuelling divisions in the country.

Oil majors including Shell, Exxon, Chevron, Eni and the state-run oil group NNPC have all been targeted by attacks this year.

The assaults have reduced Nigeria's output by a third, hammering government revenue at a time of low global oil prices.

Before the attacks, the oil sector accounted for 90 percent of the nation's foreign exchange earnings and 70 percent of government revenue.

Nigeria’s economy has also been hit badly by the global fall in oil prices since mid-2014, which has hit government revenues hard and forced up inflation to an 11-year high.

Despite the billions of dollars generated since the discovery of crude in Nigeria in the 1950s, most people live in dire poverty around the creeks and rivers of the oil-producing southern delta region. (AFP)

•Photo shows a Niger Delta militants.

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