The United States and the Philippines, after nearly a decade of intermittent negotiations, yesterday reached agreement on a $500 million aid package and new arrangements for retention of the largest U.S. military bases in Asia.

The new deal involving Clark Air Base, Subic Bay Naval Base and several smaller U.S. facilities was completed in three hours of New Year's Eve negotiations in Manila and announced in the two capitals. It is subject to approval by both governments, which is expected.

The Philippine bases agreement is the first of its kind to be negotiated during the Carter administration. At a time when the United States is establishing full diplomatic relations with the People's Republic of China and withdrawing diplomatic recognition and its remaining military forces from Taiwan, the new arrangements were described by officials here as a reaffirmation of Waskington's intention to remain a major military power in East Asia.

The base accords, which technically are amendments to agreements that run to 1991, are likely to face opposition in Congress from lawmakers questioning the need for U.S. military power in the region and objecting to human rights abuses by the government of Philippine President Ferdinand Marcos. However, State Department sources said key members of Congress have been kept informed during the negotiations.

As made public yesterday here and in Manila, major points in the new agreement include:

Affirmation of the principle of Philippine sovereignty over the bases and the waters near Subic Bay. Filipino base commanders will be named, and the Philippine flag will be flown in a position of supremacy. The United States, however, will retain unhampered use of operational areas within the bases.

A U.S. pledge to exert its "best efforts" to obtain $500 million in military and economic aid and arms sales credits from Congress over a period of five years. The total is half the $1 billion offered to the Philippines by Secretary of State Henry A. Kisinger in the closing days of the Ford administration. That amount was rejected by Manila in hopes of obtaining a better deal.

A thorough review of the base arrangements every five years. It is anticipated that the review will be the mechanism for determining U.S. aid levels for each five-year period during the life of the base agreements.

Clark Air Base is the largest U.S. military installation outside the United States, encompassing 130,000 acres. It was a major U.S. logistics center during the Vietnam war, but was not used for bombing raids because of a requirement for prior Philippine approval for combat operations. This requirement remains in effect under the amended accords.

Subie Bay Naval Base is the largest U.S. ship repair and refueling facility in the Pacific and a frequent port of call for the ships of 7th Fleet. It figured in the news recently when the U.S. aircraft carrier Constellation was ordered from there to a position closer to the Persian Gulf due to the chaotic political situation in Iran.

The bases are a legacy of the U.S. colonial domination over the Philippine Islands. The basic agreement being amended dates to March 1947, less than a year after Philippine independence was granted by the United States. A modified agreement was signed in 1966 to run for 25 years.

Negotiations for major revisions began in 1969 and have taken place intermittently since, falling just short of agreement several times. Since South Vietnam fell in mid-1975, Marcos has been more vocal in demanding new arrangements and at times has questioned the benefits of the bases to his own security.

A visit to Manila last May by Vice President Mondale led to accord on major principles embodied in the agreements reached yesterday. U.S. officials credited Sen. Daniel K. Inouye (D-Hawaii) with an important role by convincing Marcos, during a visit in October, that Congress would not approve terms much more generous than those being offered by the Carter administration.

The Philippine bases were justified for decades as outposts in a U.S. military are for the containment of communist China. As relations with Peking improved, the rationale for the bases has changed. According to Pentagon sources, the current justification is that the bases provide flexibility and efficiency in protecting vital sea lanes for the United States and its allies, a forward projection of U.S. military stakes in Asia and a possible "back-door" supply route to the Persian Gulf and Middle East in cae of military emergencies.

Due to the Sino-Soviet conflict, China has muted its opposition to a continued U.S. military presence in Asia and, behind the scenes, is reported to urge the United States not to leave the region open to Soviet power.

In July 1976, Marcos signed an agreement with Hanoi pledging that he will not allow the Philippine bases to be used for intervention in Vietnam or against other countries of the region. Marcos was quoted by news agencies as saying yesterday that the bases are for "defensive purposes" and that the revised arrangement is not intended against any countries or any group of countries.

State Department spokesman Thomas Raston said the bases "are important to our ability to project U.S. military strength throughout the Pacific" and that the agreement will "serve to preserve peace and stability in the region." CAPTION: Map, no caption, The Washington Post