US Defence Secretary Donald Rumsfeld says he is still unsure whether to extend the mission of 1,000 US troops currently training Philippine forces to combat Muslim militants in the south of the country.

The US training exercises, which began in January and saw the largest deployment of American troops outside Afghanistan since 11 September, are due to come to an end next month.

Mr Rumsfeld is also examining a proposal from the US Pacific Forces commander which includes training in smaller units better suited to tackling guerrilla groups. However, troops would be exposed to a greater risk of combat.

Rumsfeld: We haven't "got" many terrorists yet

The Philippine rebel group, Abu Sayyaf, has been linked to the al-Qaeda network and has been holding two Americans and a Filipina nurse hostage for more than a year.

Speaking on Tuesday after a visit to the country by his deputy, Paul Wolfowitz, Mr Rumsfeld said: "I've not made a decision on it.

"The mission in the Philippines has proceeded in precisely the way it was intended," he said, but he admitted there had been little progress against the rebels so far.

"You can improve the situation in one place by your presence, but unless you get the terrorists you have not improved the situation net in the world," he said, referring to the US "war on terror".

Abu Sayyaf: thorn in side of Arroyo government

"And there has been very little of getting terrorists in the Philippines thus far."

The troops, who have been based on the forested island of Basilan - the Abu Sayyaf stronghold - are authorised to train and share intelligence with local troops but not to take offensive action against the guerrillas themselves.

But Mr Rumsfeld acknowledged that the small troop patrols proposed could be drawn into fighting if they came into contact with the guerrillas.

"Anyone that would suggest that couldn't happen, I think, would just not understand how confused life can be," he said.