In an interview aired here by radio station dxRZ, Abu Sayyaf spokesman Abu Solaiman said the Islamist kidnapping group "will be your worst nightmares. We will let you feel the fear and the raging fury very deep inside us."
Asked if they would mount attacks during the Bush visit, Abu Solaiman answered, "Yes, just wait for it."
He said the attacks will "depend on the circumstances and developments," but refused to elaborate, stating "it is better for us to keep our silence about the plans."
"We would rather not comment on anything about the operational matters, just wait and see."
His threat comes before Bush’s scheduled eight-hour visit to the country on Oct. 18 in what is widely seen as a gesture of gratitude for President Arroyo’s support in the US-led "war on terror."
Abu Solaiman called on the Muslim minority in the southern Philippines to rise up and join them in their guerrilla war.
He did not say if the group would target Bush, who will be under tight security during the visit and will not venture to the South where Muslim militants are active.
The Abu Sayyaf is known mainly for kidnapping foreigners and Christians in the southern Philippines and demanding hefty ransom payments. They have also engaged in bombing attacks in the South.
The group has been linked by both Washington and Manila to the regional terrorist groups affiliated with the al-Qaeda terror network.
Military spokesman Lt. Col. Daniel Lucero said government forces were ready for any threats during the Bush visit, adding that "we continue to hunt down the remaining rebels in then southern Philippines."
Abu Solaiman was one of five Abu Sayyaf leaders who had bounties of up to five million dollars placed on their heads by the US government for the kidnapping of three Americans, resulting in the deaths of two of them.
Abu Solaiman also said the Abu Sayyaf will avenge the death of one of their members, Buyungan Bungkak, who was shot dead Tuesday in the police headquarters in Manila after he killed three policemen during an escape attempt.
"There will be justice," he said.
Meanwhile, the US Embassy in Manila announced that the two countries would sign next week a memorandum of intent to strengthen cooperation and "enhance the anti-terrorism capabilities of the government of the Philippines."
The memorandum would set guidelines for countries that receive anti-terrorism assistance from the United States.