Nairobi/Abuja  - A 60-day amnesty for militant groups in Nigeria's restive Niger Delta came into effect on Thursday - a move the government hopes will end attacks on oil facilities.

Nigeria's main militant group the Movement for the Emancipation of the Niger Delta (MEND) has conducted a long-running campaign of sabotage in the oil-producing Niger Delta, cutting the West African nation's oil production by over 20 per cent since early 2006.

President Umaru Yar'Adua in late June unveiled the amnesty, offering a presidential pardon, education and training to those who lay down their arms within that period. One of MEND's leaders Henry Okah, who was arrested in Angola in 2007 on charges of treason and gun-running, was also released.

However, it is not yet clear if MEND or other groups will officially take up the offer.

MEND has said it will cease all attacks during the amnesty period and admitted that one of its commanders, Ebikabowei Victor Ben - known as Boyloaf - was in talks to return to civilian life.

However, MEND said it would wait for ongoing negotiations to be completed before revealing its intentions.

"When we choose to disarm, it will be done freely; knowing that the reason for our uprising , which is the emancipation of the Niger Delta from neglect and injustice, has been achieved," MEND spokesman Jomo Gbomo said in an emailed statement.

Militants operating in the delta say they are fighting for a larger share of the wealth for local residents, who complain the oil industry has ruined their agriculture and fishing livelihoods.

However, illegal bunkering - the practice of tapping into oil pipelines and selling the crude on the black market - takes place in the background of the conflict.

Many of the gangs are backed by businessmen and politicians, who are believed to make millions of dollars each day from siphoning off oil.

Analysts say that the amnesty deal, which is not the first such offer, may not seem particularly tempting with such huge sums of cash on offer.

Nigeria is Africa's most populous nation, with around 150 million inhabitants. Despite its massive oil wealth, most Nigerians live in poverty. (dpa)