An offer of amnesty for Nigerian militants waging attacks in the oil-rich Niger Delta has been met with mixed reviews and prompted increased criticism of President Umaru Yar'Adua's handling of the ongoing violence in the region.

Earlier this month, Yar'Adua shocked many Nigerians when he extended the proverbial olive branch to the delta's armed groups, saying he would grant the gunmen amnesty if they agreed to lay down their arms and partake in talks.

"We will grant amnesty to all those who are ready to lay down their arms," Yar'Adua said. "It will also include rehabilitating and integrating them into the system."

The president said that his security chiefs were working out details of the planned talks, though no definitive plan for engaging militant leaders has been offered.

Nigeria's leading militant group, Movement for the Emancipation of the Niger Delta, denounced the proposed amnesty offer.

In an e-mail from MEND sent to Nigerian news sources, the group said it would not "lay down its arms because of a mere verbal statement from Mr. Yar'Adua" but would consider talks with the government under the auspices of an international mediator.

So far, the offer to MEND has received mixed reviews from hard-line members of the Nigerian government, who favor continuing the current military tactic of dealing with militants. The Nigerian army's Joint Task Force operating in the delta deals exclusively with the handling of the region's militant and gang violence, which has been blamed for the more than 25 percent shortfall in oil production in recent years.

Nigerian oil output had once reached about 2.5 million barrel per day. According to recent estimates by the country's oil officials, output has dropped to about 1.6 million bpd in recent weeks, a reduction blamed on attacks on oil and gas installations by armed groups and kidnapping of petroleum workers.

Last month, the Nigerian government announced that it was ramping up security in the region, but little effect has been noted in reducing the violence directed toward the petroleum industry.

A recent report by government and private observers in the delta found that at least 1,000 people had been killed in militant-related violence in 2008. The violence also cost the sector more than $20 billion in lost production, according to the findings.

Nigeria's militants contend their ongoing fight against the oil industry is based on the inequitable distribution of the country's oil wealth. Though the delta has produced more than $300 billion in oil over the last few decades, much of the region remains impoverished and underdeveloped.

However critics of MEND and other militant groups in the delta say their cause is bent on nothing but thievery, pointing to their practice of siphoning oil from the country's pipelines and selling it on the international black market.

Yar'Adua's new tact for handling the difficult delta situation follows his decision last week to replace six of the top officers at the country's state-run petroleum company, the Nigerian National Petroleum Corp.

Additional changes to the governing body for Nigerian oil and gas are expected in the coming weeks and months.

The across-the-board changes to the sector come ahead of the new proposed petroleum bill that has been sent to the Nigerian National Assembly.

The call for reform of the Nigerian oil sector comes at a time when the industry is faced with production far below 2 million barrels per day, placing the industry second among African oil exporters, behind Angola. Heading a long list of proposed changes to the sector is the ability for the NNPC to solicit private funds for investments in joint ventures with foreign energy firms, ending the longstanding policy that required the NNPC to ask the federal government directly for capital.