U.S. armed forces will have expanded use of military bases in Singapore under an agreement signed Tuesday after two years of negotiations.

The new arrangement comes as U.S. and Philippine officials negotiate the future of six American bases that have long been the Pentagon's anchor in Southeast Asia. The bases' leases expire next year."The agreement will permit the enhanced use of facilities for American ships and aircraft and will facilitate a robust U.S. presence in the Pacific," Vice President Dan Quayle said at the signing ceremony in Tokyo.

The accord was also signed by Singapore's Prime Minister Lee Kuan Yew, who leaves office next month.

Quayle and Lee were in Tokyo for the enthronement of Emperor Akihito.

Under the pact, the Air Force will be permitted to send aircraft to Singapore several times each year on training deployments of several weeks each, a U.S. Embassy statement said.

More U.S. Navy vessels will also visit the tiny island-nation about 1,450 miles southwest of the Philippine capital of Manila.

About 95 Navy and Air Force personnel will be assigned to Singapore year-round, and about 75 Air Force personnel will rotate through Singapore on each training deployment, the statement said.

The statement said the increase will start in the next three to six months at Paya Lebar Airport and the port at Sembawang.

"I think the agreement shows the determination of the United States to retain a presence in Asia . . . (as a) key to economic and political stability in this region," said a U.S. official, speaking on condition of anonymity at a briefing.