A group of United States Federal agents has arrived here from Manila and met top Philippine military officials to discuss the progress of the government operation to free two Americans held by the Abu Sayyaf group in Basilan province, a local radio station reported yesterday.

Local military officials would not give details of the meeting, but Radio Mindanao Network reported that members of the U.S. Federal Bureau of Investigation and the Central Intelligence Agency had gone to the Southern Command on Thursday.

The Americans reportedly arrived on a private jet at the military's Edwin Andrews Air Base, but Philippine Air Force officials would neither confirm nor deny the report.

The meeting was believed to have centred on the ongoing military rescue efforts to free U.S. missionary couple Martin and Gracia Burnham, who have been held hostage by the Abu Sayyaf guerrillas since May 27.

The Moro rebels seized the Burnhams during a raid on the upscale Dos Palmas beach resort in the central Philippine province of Palawan, some 950 kilometres southwest of Manila.

This was not the first time that U.S. officials had arrived here, following serious concern expressed by Washington on the safety of American hostages and what the U.S. described as the slow progress of the rescue operation.