Secretary of State Edmund S. Muskie said yesterday that "everyone concerned now agrees that it was a regrettable omission" that the State Department did not participate in drawing up a new U.S. nuclear weapons strategy, and suggested that the omission will not be repeated.

Muskie did not say explicitly whether he has a firm commitment from President Carter about future involvement in nuclear war targeting, which Muskie said "is at the heart of our ability to enforce the doctrine of deterrence in hope of avoiding nuclear war." But the secretary of state said that "I suspect" that from now on his department will not be excluded.

Muskie spoke in similar interviews on Nbc's "Today" program and ABC's "Good Morning America." By early afternoon, however, the State Department still did not have a copy of Presidential Directive 59, the nuclear war strategy document that has caused a public fuss, although Muskie was briefed about its contents Monday by a Defense Department official.

The recollections of a former high State Department official as well as government records available yesterday suggested that the "regrettable omission" in this case may have been deliberate rather than accidental.

Leslie H. Gelb, who was director of the State Department's Bureau of Politico-Military Affairs in the first 30 months of the Carter administration, said the State Department only learned through the informal Washington grapevine that the White House had launched a nuclear targeting study, and that efforts to become involved in it were repeatedly rebuffed over a period of many months.

"What was at issue was not the policy, which I don't think would have caused a serious dispute, but the principle of denying the president alternative points of view," said Gelb.

Gelb said he could recall only three intergovernmental meetings on nuclear war strategy involving State. Departmental records checked in response to a press inquiry also turned up only three such meetings, all around April 1979. State Department officials said several efforts by departmental officers to become involved in or informed about the ongoing policy-making on the issue since the spring of last year were rebuffed.

Former secretary of state Cyrus R. Vance, however, reached at his New York law office, said he had had several private conversations about the war doctrine with Secretary of Defense Harold Brown and presidential assistant Zbigniew Brzezinski and that he believes he was adequately consulted on the "principles" behind the policy.

But Vance also said he would not quarrel with Gelb's account of the difficulty of State Department involvement on the staff level.

Vance said the secretary of state definitely should be involved before a directive goes out on a subject with such weighty foreign policy consequences. Referring to the fact that Muskie knew nothing of the substance of the new directive before reading about it in the newspapers, Vance said. "I would be concerned if I were in his shoes."

Muskie, on the other hand, said on "Good Morning America" that "the quality and the quantity of the participation [in the war doctrine] of the State Department . . . predating, I emphasize, my service as secretary of state was, in my judgment, inadequate." Muskie said he has communicated this view to the other agencies involved and that "there is agreement, I think" on this point.

According to an account in yesterday's editions of The New York Times, the nuclear war study, after a period during which it lay dormant, became active at the top levels of the White House and Pentagon this June, a month after Muskie replaced Vance. The Times account said that in addition to Brzezinski and Brown, only a handful of their respective aides were involved, and that Brzezinski and Brown met with the president late in July to obtain his approval of the nuclear war directive.

During this period of final activity, Muskie met four times for regular three-cornered discussions to coordinate policy with Brzezinski and Brown, at lunch on June 11, breakfast on July 3, lunch on July 17 and in a meeting of the three of them July 24 at the White House.

In Muskie's account, however, the first time the new nuclear directive was mentioned to him was at a lunch with Brzezinski and Brown on Aug. 5, and then in such a way that Muskie did not obtain the impression that it already had been signed by Carter.

Carter actually signed the directive Friday, July 25, according to official sources. Muskie had met Brown and Brzezinski the day before, without hearing about it. The day of the signing, the three top national security officials participated together in their regular Friday breakfast with Carter, evidently with no reference to the nuclear war strategy directive being presented to the president for signature.