Reagan administration officials said yesterday that advance notification of Congress prior to U.S. military strikes against Libya was not required by the War Powers Resolution of 1973, and President Reagan said that U.S. forces in or near the Gulf of Sidra took only "limited measures of self-defense necessary to protect themselves from further attack" after coming under hostile fire.

"We will not be deterred by Libyan attacks or threats from exercising our rights on and over the high seas under international law," Reagan wrote to leaders of the House and Senate. "If Libyan attacks do not cease, we will continue to take the measures necessary in the exercise of our right of self-defense to protect our forces."

In a separate letter to House Foreign Affairs Committee Chairman Dante B. Fascell (D-Fla.), White House assistant for congressional relations William L. Ball III contended that U.S. actions in the disputed Gulf of Sidra did not require advance notification under the war powers act. Ball said the law was not "intended to require consultation before conducting naval maneuvers in international waters or airspace."

Fascell said Monday that the president should have notified Congress beforehand because hostilities were "a distinct possibility" when U.S. forces entered an area claimed by Libyan leader Muammar Qaddafi.

But administration lawyers did not accept this contention. A senior official said that the language of the act requires notification only in the event that "imminent hostilities" are likely. Officials dispute that this was the case in the gulf, pointing out that U.S. forces have entered it on many occasions without provoking action by Qaddafi.

While maintaining that notification was not legally necessary under the law, officials said the letter Reagan sent to House Speaker Thomas P. (Tip) O'Neill Jr. (D-Mass.) and Senate President Pro Tempore Strom Thurmond (R-S.C.) would meet the requirements of another provision of the law mandating a report to congressional leaders after a hostile exchange.

The letter did not refer to the War Powers Resolution, which is intended to make deployment of U.S. forces in hostile situations subject to congressional approval. Once the president notifies Congress that hostilities are imminent under provision of the act, Congress would have to agree to any commitment of troops beyond 60 days. The president would have an additional 30 days to withdraw the troops.

The administration's legal position that the act does not apply was consistent with the view it took when U.S. military advisers were sent to El Salvador, Marines were deployed in Lebanon and when U.S. forces invaded Grenada. It was also consistent with the positions taken by Presidents Gerald R. Ford and Jimmy Carter in similar situations.

Only Fascell, who was traveling yesterday and unavailable for comment, objected publicly to the lack of advance notification in the Gulf of Sidra operation. But there was a widespread call from Congress in 1983 for use of the War Powers Resolution after the Grenada invasion. Reagan refused to invoke the law but withdrew U.S. troops within 60 days.

The War Powers Resolution was passed on Nov. 7, 1973, after a bitter battle between President Richard M. Nixon and a Congress trying to recapture some of the authority it had yielded in passing the 1964 Gulf of Tonkin resolution, which President Lyndon B. Johnson invoked in escalating U.S. involvement in Vietnam.

Every president since then has opposed the law as an infringement on his constitutional authority as commander in chief of the armed forces.

Reagan made this point again in the letter he sent to the congressional leaders, which was dated on Wednesday and made public by the White House yesterday.