CAMP DARAPANAN, THE PHILIPPINES - US ambassador Kristie Kenney on Tuesday met with the head of the Philippines' main Muslim rebel group in an attempt to re-start stalled peace talks, the two sides said.

Accompanied by US security personnel and aid officials, the envoy visited the main rebel base of Camp Darapanan and met with Muhammad Murad, chief of the separatist Moro Islamic Liberation Front (MILF).

She said it was a "private visit" and would not comment further.

Washington has pledged tens of millions of dollars in aid to the troubled Mindanao region of the southern Philippines once Manila strikes a peace treaty with the 12,000-member MILF.

Concerned with the rise of Islamic fundamentalism in Southeast Asia and the previous use of MILF training camps by Jemaah Islamiyah (JI) militants, the US government is also providing military training and intelligence to Filipino forces in the southern Philippines.

The visit came as the Philippine military announced it has exhumed in the nearby Tawi-Tawi island group what it believes could be the remains of key JI suspect Dulmatin, a principal suspect in the 2002 Bali bombings.

"We are on track. We negotiating now so we can achieve the aspirations of the (Filipino Muslims). We are trying very hard to get the peace agreement that we want," Murad told AFP.

Representatives of the MILF and President Gloria Arroyo's government met earlier this year to discuss the talks, which are hosted by Malaysia, he said.

"We are just discussing some issues now and we are returning to the peace table in March," he added.

Kenney was greeted by MILF fighters in combat uniform and armed with M-16 rifles and rocket-propelled grenades. She met with Murad behind closed doors for about an hour before departing.

"We have to build peace on the ground first while negotiating," Murad said, adding that the US Agency for International Development "is helping us in building this aspect of the peace process." MILF officials told AFP that Kenney asked the MILF to support annual joint military exercises between US and Filipino troops. This year's maneuvers began in several areas of Mindanao on Monday.

Michael Mastura, member of MILF peace panel, said the peace talks with the Philippine government were back on schedule but said there were some "obstacles relating to the ancestral domain issue."

"We would have to see whether we can reach a political settlement on the ancestral domain issue," he added.

The completion of a final peace agreement between the government and the MILF hit a snag in December due to disagreements over the issue of "ancestral domains" or government recognition of areas where the country's Muslim minority would have some control.

The MILF has been waging a bloody rebellion in the mineral-rich Mindanao island since 1978, but signed a truce with Manila in 2003 paving the way for
peace talks.

Several thousand US troops began arriving in the southern Philippines on Monday to take part in the annual military exercises with the Philippines.