By Clive Myrie BBC Asia correspondent in Davao, the Philippines

American troops have completed their withdrawal from the Philippines after six months providing training and advice to the country's army in its fight against Muslim separatists.

About 1,000 US military advisers and support units have been based in the southern Philippines where a rebel group, the Abu Sayyaf, has been waging a guerrilla war for the last two years.

Washington says the rebels have links to Osama Bin Laden's al-Qaeda and plans more troop exercises in the Philippines.

Some view the US presence as unwanted foreign interference

American soldiers came to the Philippines in January as part of President Bush's war on terrorism, part of the noose spread worldwide around the nets of extremist Muslim groups with perceived links to Osama Bin Laden.

The Abu Sayyaf have been a painful thorn in the side of the administration of Philippines President Gloria Arroyo, terrorising the south of the country and a swathe of the South China Sea, kidnapping and committing murder in what they say is a fight for a separatist Muslim state.

Technical support

US instructors who usually train Green Berets, military engineers and support personnel have been helping local troops tackle the Abu Sayyaf.

In one attack, American technical surveillance pinpointed the whereabouts of a prominent guerrilla leader who was later assumed to have been killed.

Despite being welcomed here by many Filipinos, the US military presence has angered others who rejoiced in 1991 when the Senate voted to shut down a naval base here, ending nearly 100 years of American military presence in this former US colony.

Campaigners say they will hold demonstrations this weekend. They are angry at an agreement to be signed on Saturday in Manila with the visiting US Secretary of State, Colin Powell.

The deal will allow American military advisers to return permanently to the Philippines, ostensibly to help in the war against Muslim extremists.