Senior members of the House International Relations Committee have expressed concern to President Carter about an apparent shift in U.S. policy toward the Soviet Union and asked him ot clear up "confusion and doubt" resulting from conflicts within the administration.

Chairman Clement J. Zablocki (D-Wis.) and a broadly representative bipartisan group of subcommittee chairmen an prominent members conveyed their views in a letter to Carter after a series of unpublicized meetings. Their statement came after several weeks of high-level infighting over U.S. reactions to Soviet and Cuban activities an widespread speculation that the "Cold War" of previous decades is being revived.

The letter, signed by 14 lawmakers, was authorized in a meeting Tuesday, the day before Carter sought to clarify his foreign policy in a speech at the U.S. Naval Academy graduation exercises. However, the letter was finished and sent to the White House Thursday night, the day after Carter's address, and several members said their doubts and apprehension remain.

The lawmakers expressed particularly concern about recent statemants by national security affairs adviser Zbigniew Brzezinski, saying that "we do not understand the meaning or intention" of his strong stands about Soviet activities, "nor do we know the motivation for this development."

A related focus of inquiry was suggestions that the strategic arms limitation talks (SALT: or other U.S. relations with the Soviet Union might be affected by Soviet and Cuban activities in Africa and elsewhere. "There is concern in the committee whether it is in our own national security interests to permit developments in Africa to adversely affect our overall relations with the Soviet Union," the lawmakers said.

Reflecting the current state of uncertainty about which set of officials is directing U.S. foreign policy, the lawmakers asked Carter to make available Secretary of State Vance or whoever you determine is best able to articulate the significance of these developments and whether there has been a change in U.S. policy or whether any change is contemplated.

There is confusion and doubt as to just what our policy is with respect to several critical areas of foreign policy," lawmakers told Carter, saying that this makes it more difficult for them to work effectively to support the administration efforts. "Many members of Congress are embarrassed by their current inability to answer questions from their constituents as to what is U.S. policy on such issues as Soviet-American relations and Africa," the letter said.

Concerning White House complaints that legislative restrictions tend to tie the president's hands on foreign policy, the commitee promized to review "on a priority basis" any requests from Carter to repeal or modify laws "which you believe unduly constrain in your conduct of foreign policy." However, the committee said it must have specific recommendations and justification for them before it can consider action.

Zablocki said yesterday in a telephone interview that the consessus of his committee is that the White House, rather than Congress, should take the initiative in recommending what to strike from lawbooks concerning any foreign policy provisions that unwisely impede presidential action. Many of the most important restrictions - such as the War Powers Act - flowed from conflict between Congress and the White House during the Vietnam war.

Zablocki said the committee sent a copy of its letter to House Speaker Thomas P. (Tip) o'Neil Jr. (D-Mass.) with a report saying the White House should make specific requests if it desires major changes in the law.

The committee had previously agreed to delete a number of minor or outdated restrictions on executive action along with one major restriction - the U.S. arms embargo on Turkey, which Congress passed over Ford administration objections.

The House committee, as the letter to Carter noted, has supported most of the president's foreign policy positions, and the signers represent a broad spectrum of political opinion within the committee. This adds considerably to the potential impact, and the significance, of the letter.

Only those members who had been involved in recent discussions about legislative restrictions were invited to sign the letter. In addition to Zablocki, the Democratic signers included subcommittee chairmen Jonathan B. Bingham (N.Y.), Charles C. Diggs Jr. (Mich.), Dante B. Fascell (Fla.) and Donald M. Fraser (Minn.).