President Reagan today lifted the suspension of military aircraft deliveries to Israel without having made a finding whether Israel violated its agreements with the United States when it bombed a nuclear plant in Iraq on June 7.

Secretary of State Alexander M. Haig Jr. said that the 16 warplanes affected by the suspension would be on their way to Israel "in a matter of days or hours" but said that the "intensive" government review had failed to determine whether Israel's bombing raid had been defensive or offensive.

The decision came at a three-hour National Security Council meeting, the bulk of which was devoted to discussion of strategic defense systems, including the MX missile and B1 bomber, according to White House counselor Edwin Meese III, who attended.

Meese refused to indicate how the president is leaning on the crucial defense questions and said Reagan's decisions will be made in three to five weeks.

In explaining the warplane decision, Haig told reporters: "I think one, in a subjective way, can argue to eternity as to whether or not a military action may be defensive or offensive in character." Israel has pledged not to use U.S.-supplied weapons for offensive operations.

Haig indicated that the administration was influenced by Israel's willingness to enter into the current cease-fire in Lebanon. "The administration, in its review, has also taken account of events and trends in the Middle East, particularly the events in Lebanon leading to a cease-fire there," Haig said.

Delivery of four F16s was withheld June 10 after the raid in Iraq. Just as the administration was preparing to lift the embargo in mid-July, an Israeli air raid on central Beirut drew widespread criticism in the Middle East and United States, and the embargo was extended to six additional F16s slated for delivery. Last week, four more F16s and two F15s were withheld as the suspension continued.

Reagan has been under intense Israeli pressure to resume the aircraft deliveries. Last Sunday, Israeli Prime Minister Menachem Begin called the suspension "unjustified and unjustifiable." The planes being withheld "are Israeli planes," Begin said.

Haig said the review of the implications of the Israeli raid in Iraq included candid discussions with Begin and Ephraim Evron, Israeli ambassador to the United States.

In Washington, Evron issued a statement welcoming release of the "American-manufactured airplanes acquired by Israel" but added that the suspension had been "unhelpful and unjust." The new decision will lead to strengthening of traditionally close Israeli-American ties, Evron said.

"It wasn't necessary to make a legal or juridical decision," Haig replied when asked whether the Israeli raid had been determined defensive or offensive.

Haig said that Israel has given no new assurances about use of American military equipment but that the administration and Israel clearly understand the terms of the U.S. military assistance.

Asked how he thinks the suspension has affected U.S.-Israeli relations, Haig said: "I wouldn't presume to comment on how it's affected our relationship with Israel. We don't see any change in our longstanding relationship."

Relations between the administration and Israel have become increasingly strained, and the suspension of warplane deliveries was the lightning rod attracting the most intense Israeli criticism. The Israeli mood arises from a general feeling that Washington is insufficiently sympathetic to Israel's problems with its Arab neighbors.

Asked what has changed since the suspension was imposed, Haig said:

" . . . There has been an extensive suspension. There has been extensive communication between ourselves and the government of Israel. There has been consultation with Congress. There has been a thorough review, directed by the president, with respect to the circumstances of the initial raid.

"There have been, as you know, complicating circumstances in the Middle East, an escalating level of violence, which was concluded as a result of cooperative efforts by all of the parties and the so-called 'cessation of hostilities' which has occurred between Lebanon and Israel. All of these factors went into the president's decision . . . . "

Haig said there is "absolutely no linkage" between today's action and the administration's plan to send sophisticated radar surveillance planes to Saudi Arabia. He also denied any link to Begin's scheduled visit to Washington early next month.

Today's NSC meeting was held in the Century Plaza Hotel after Reagan flew by helicopter to Los Angeles this morning from his Santa Barbara ranch where he spent 10 days. He will be in Los Angeles until the weekend, when he will return to his ranch.

Joining Haig and Meese at the meeting were Defense Secretary Caspar W. Weinberger, White House National Security Adviser Richard V. Allen, Joint Chiefs of Staff Chairman Gen. David C. Jones, Air Force Chief of Staff Gen. Lew Allen Jr., CIA Director William J. Casey and White House Chief of Staff James A. Baker III.

Meese said Allen made his first presentation to Reagan on the MX. The Air Force strongly opposes basing the MX in aircraft, a plan that has attracted the attention of Weinberger and other administration officials, in part because it would be cheaper than a land-based system and in part because it would not require extensive environmental damage to a large land area for construction of silos and roadways.

Charles Townes, head of a committee appointed last March by Weinberger to study alternative basing possibilities for the MX, also attended. The air-based option was among proposals made by that committee. Also here were Arms Control and Disarmament Agency Director Eugene V. Rostow and Ambassador to the U.N. Jeane J. Kirkpatrick.

Meese called recent news reports that Weinberger now seeks to defer an MX decision "erroneous."

He said that the strategic planning meeting and a budget meeting planned Tuesday are not linked directly. "Cost is not a limiting factor," Meese said of the administration's strategic planning.