Government negotiators were locked in talks with the rebel leaders inside a high rise in the Makati financial district as the ultimatum lapsed at 7:00 pm (1100 GMT). An Arroyo aide said there was no sign any of the estimated 150 rebels inside would yield soon.

Senator Gregorio Honasan, suspected by the government of supporting the rebels, said government envoy Roy Cimatu, a former armed forces chief, was still in discussions with the mutineers.

Honasan, a former army colonel who led a series of coup attempts in the 1980s, told reporters after emerging from the same meeting he understood that "while Ambassador Cimatu is inside, the deadline is extended indefinitely."

There was no official word from the government.

Reporters on the scene said there were no signs of an impending assault as night fell.

WAR.WIRE