The Carter administration would consider the idea of periodic "consultative" meetings with Soviet leader Leonid I. Brezhnev, even if they produced no immediate aggreements, national security adviser Zbigniew Brzezinski indicated yesterday.

Presidential adviser Brzezinski's concept, aired at a breakfast meeting with reporters, went beyond the administration's pervious position on Carter-Brezhnev summit conferences. It raised a new approach for trying to cut through the impasse on nuclear strategic arms limitation talks (SALT).

Brzezinski said this idea was not discussed in President Carter's meeting on Tuesday with Soviet Ambassador Anatoliy F. Dobrynin. But Brzezinski yesterday continued the discussion on the SALT stalemate by invitating Dobrynin to the White House for lunch.

Chief U.S. arms control negotiator Paul C. Warnke, in a CBS television interview Sunday, said the administration drive for drastic cuts in nuclear forces "could very well involve" a Carter-Brezhnev meeting. Brzezinski went further yesterday to discuss a basic new pattern of possible meetings.

Brzezinski noted yesterday that "there is generally a presumption that there would be a (Carter-Brezhnev) meeting this year."

Such a summit meeting, however, had based on the belief that it would climax negotiations for completing a new nuclear arms accord. Since the U.S.-Soviet SALT negotiations foundered in Moscow two weeks ago, administration strategists are looking for new ideas. Now summit talks are now being considered to help to accelerate negotiations

The usual American-Soviet summit conference, Brzezinski pointed out, carries the hazard of being dramatic expectations, with [WORD ILLEGIBLE] to produce hasty agreeements [WORD ILLEGIBLE] a bad diplomatic rebound if they do not materialize.

Brzezinski said "it would generally be a good idea to decouple meetings between the U.S. President and Soviet leaders" from expectations of immediate settlement. He said "a Carter-Brezhnev meeting would be useful without an agreement," in "a consultative" mode.

When asked if that is a personal view or an administration position, Brzezinski replied, "I think the idea of having regular meetings is generally accepted." On the question of whether it is wise to link such meetings to expectations of agreement, Brzezinski said, "my view is that this is not helpful."

Brzezinski stressed yesterday what he described as the "mind-boggling" complexity of the current SALT negotiations.

In the wake of the setback in Moscow, although the Carter administration officially declines to describe the encounter in those terms, Brzezinski talked about "the terribly difficult" task of achieving a meeting of the minds between Moscow and washington on what the Carter administration calls "real arms control."

Brzezinski said the United States is now seeking a "clearer and more precise" definition of Soviet objections to the rejected U.S. proposal for breaking the SALT impasse.

". . . This is a prolonged, difficult process in which patience is really necessary," Brzezinski said. Neither side, he said, is talking the view that it is confronted with a "a take-it-or-leave-it proposition."

Brzezinski said he believes that the concurrent U.S. Soviet tangle over fishing rights off the American coast, with the U.S. detaining two Soviet vessels, can be dealt withe on its own merits. ". . . We have tried to takes a restrained position on this subject," Brzezinski said Most Soviet fishing ships are complying with American regulations he said, and "I hope we can isolate if from the (basis) U.S.-Soviet relationship."

The Carter administration, Brzezinski indicated now wants to tone down public crossfire with the Soviet Union over SALT, and negotiate in private. "The latter," he said, "clearly has to be done under discreet conditions."

That was the setting for Soviet ambassador Dobrynin's second trip to the White House in two days.

The Brzezinski-Dobrynin form was lunch in the former's office with the "daily special" from the White House mess; roast beef, apple pie a la mode, an no disclosures. Spokesman Jerrold L. Schnecter labeled "it a working meeting," part of a continuing process" of discussions.

Defense Secretary Harold Brown, in a speech prepared for a University of Rochester audience last night, also sounded the current, conciliatory U.S. theme, with some identical phraseology: "The proposals we have made are reasonable and equitally, but they are not presented as sake it-or-leave it propositions."

". . . We are willing to listen to their (Soviet) arguments and consider adjustments to our own proposals that would not affect the equitable out-comes our two proposals are designed to achieve.

Brown also said that if the Soviet Union should avoid as agreement and those the upward path and continue to increase the size and effectiveness of their strategic forces," the American "resource base is large enough to ensure that the Soviets cannot gain political and military advantages over us."