LAGOS (Reuters) -- Militants whose raids have cut Nigerian oil exports by a quarter threatened to attack state governors from the Niger Delta region, accusing them of betraying their people's interests.

Most state governors in Nigeria's far south have defied popular opinion and joined a campaign to amend the country's 1999 constitution to allow President Olusegun Obasanjo to stand for a third term in 2007 elections.

The governors in the campaign are counting on another four years in office themselves if Obasanjo wins.

"The governors of the Niger Delta states are deliberately sabotaging the struggle for the liberation of the Niger Delta for selfish reasons such as greed and rule extension," the Movement for the Emancipation of the Niger Delta (MEND) said in an email to media. "They will not be missed by the people of the Niger Delta and we will make significant attempts on their convoys."

MEND militants have staged a series of crippling attacks and kidnappings against the oil industry in Nigeria's far south since December, and detonated two car bombs in April. Oil companies have cut oil production by 550,000 barrels per day, or a quarter of Nigerian output.

The militants repeated previous threats to launch more attacks on oil installations in the world's eighth largest exporter, and warned workers to stay away from the region. MEND wants to halt Nigerian oil exports completely and renegotiate control of the country's oil wealth with the central government.

They have also demanded the release of two jailed leaders from the delta, and $1.5 billion in compensation to delta villages for oil pollution.

Their campaign comes at a time of heightened tensions nationwide over the "third term campaign", which has been widely rejected by the public in Africa's most populous country.

Many delta activists argue the top job should go to that region in 2007, because it has never produced a president despite its pre-eminent economic importance.

MEND's campaign is rooted in deep-seated resentment among deltans that decades of oil production have left the region overcome by poverty and pollution.

Rampant corruption and neglect have eroded trust in government in Nigeria, where elected office even at state level comes with discretionary powers over millions of oil dollars every month.

The federal government is keen for oil companies to return to their abandoned oilfields in the vast region of mangrove-lined creeks, but the companies want to see a truce with militants first.

Obasanjo has tried to address some of the region's problems by promising to build a big new motorway through the inaccessible region, and create thousands of new jobs, but this has been rejected by MEND.