Filipinos oppose the participation of American soldiers in the campaign against the southern Philippines-based group, Abu Sayyaf, a recent survey by the Ibon Foundation said even as an advance team of American troops arrived in Zamboanga City onboard US Air Force C-130 cargo planes from Okinawa, Japan yesterday.

In a survey conducted from November to December, Ibon said 52. 73 per cent of 1,136 respondents from various sectors of society said that they are against U.S. military participation in the anti-Abu Sayyaf drive by the Philippine government.

It added that 40.32 per cent approved of U.S. military action. The same survey said most of the residents of Metro Manila favoured U.S. participation with 48.44 per cent compared to 42.67 against.

The study was conducted to determine Filipinos' perception in what is considered as the first intervention of any foreign country in local security matters in half a century.

More than 160 US troops are expected to be deployed in southern Philippines‚ Basilan province where the self-styled independence fighters, the Abu Sayyaf, are holding hostage two American missionaries and a Filipina nurse for close to seven months.

Manila has said that the U.S. forces in Basilan and Zamboanga City, which is part of a contingent of 600 to be deployed in other parts of the country, will be there purely to give training and weapons familiarisation to Filipino soldiers.

However, Philippine Defence Secretary Angelo Reyes said the foreign troops may take part in "test missions" against the extremist rebel group.

The pronouncement further fuelled speculation that the American contingent, composed of mainly special anti-terrorist and hostage rescue units, would conduct an operation to recover the three Abu Sayyaf prisoners.

Critics say the presence of the US troops violates the Constitution, and activist groups are demanding their pullout.

But the Department of Justice has said the U.S. presence was consistent not only with the Constitution but also with two military treaties between the Philippines and the U.S.

U.S. soldiers arrived in three small batches at the Philippine Air Force (PAF) Edwin Andrews Air Base, about 4 km from downtown Zamboanga City, but officials would not say the exact humber of U.S. troops that arrived here.

President Gloria Macapagal-Arroyo's spokesman, Rigoberto Tiglao derided the recent survey by Ibon as "farcical."

"We appeal to this administration's critics not to debase one of the most modern tools of democracy ' the opinion poll' for their selfish political agendas and their ideological biases," he said.

Tiglao said Ibon is "an ideologically-biased interpreter of data. It has been an unabashed propaganda group of the Communist Party of the Philippines which has been disseminating manifestos disguised as news reports," he said.