The United States, breaking three days of official silence, expressed "regret" yesterday about the Israeli cabinet's latest pronouncement on Middle East peace issues, and a prominent pro-Israeli senator condemned the cabinet statement as "the wrong signal, at the wrong time."

The U.S. declaration, made public by State Department spokesman Hodding Carter III, was mild in tone and language and expressed determination to continue the search for peace despite the disappointment caused by last Sunday's Israeli statement.

Sen. Jacob K. Javits (R-N.Y.), who is usually among Israel's firmest friends on Capitol Hill, was less reticent. In a speech prepared for Senate delivery today and made public last night he said Israel faces "a real danger" if it fails to produce a more forthcoming statement of its position. He called on the cabinet of Prime Minister Menachem Begin to accept United Nations Resolution 242 as "the firm basis for negotiation."

The territory-for-peace bargain embedded in Resolution 242 is at the heart of the dispute over the peace process. The Begin government, despite opposition within Israel and pressure from the United States, has refused to agree in principle to withdraw from the occupied West Bank in the context of a Middle East peace agreement.

Last Sunday's cabinet statement was issued in response to U.S. questions about Israel's view of the final status of the West Bank and Gaza Strip following a five-year period of "administrative autonomy" proposed by Begin. After weeks of intense debate on the question, the Israeli cabinet, in effect, said that the West Bank's future should be discussed and decided after the five years of the Begin plan are over.

This answer fell far short of what U.S. officials say is necessary in order to break the current deadlock in the negotiations with Egypt.

"We have now had time to reflect on the Israeli replies, and we have also received a full explanation on the cabinet decision from Foreign Minister (Moshe) Dayan. We regret that the Israeli replies did not fully respond to our questions," said a written comment of spokesman Carter.

Carter went on to say that the United States has been holding discussions with Egypt about its ideas on the West Bank-Gaza issues and will now be "undertaking active consultations" with both Egypt and Israel about next steps in the negotiations.

Informed officials said it should be known by early next week at the latest, on the basis of talks in Jerusalem and Cairo, what the next step will be. Among the possibilities under consideration are a new face-to-face meeting between Egypt and Israel and new trips to the area by Secretary of State Cyrus R. Vance and/or Special Ambassador Alfred L. Atherton Jr.

The planned ceremonial trip to Israel June 29 to July 3 by Vice President Mondale may also play a role. Although officials emphasized that Mondale is not going as a negotiator, he is being accompanied by several policy-level officials of the State Department and National Security Council.

U.S. officials expect that within a short period of time Egypt will make known in definite form its proposals for a negotiated Middle East settlement. Such Egyptian proposals have been under discussion between the United States and Egypt for many weeks.

Officials denied accounts, being circulated yesterday by allies of Israel, that the United States had received highly negative replies to questions which it had put to Egypt on behalf of Israel but had failed to pass on this information.

Javits' speech, while highly critical of Israel also criticized Sadat as well as the leadership of Jordan and Saudi Arabia for failing to carry forward their part of the peace process. Javits said Sadat has failed to answer the prime questions about the substance of his negotiating positions.

Unless Israel is more forthcoming in its statements about the nature of a negotiated settlement, Javits declared, "the United States may well come forward with its own peace plan." He said this would raise the issue of a dictated U.S. peace.

Explaining the sense of urgency which prompted him to call publicly for Israel to reconsider its views, Javits said "time is only on the side of those who seek anarchy or war in the Mideast, not peace." He said it is now "the high duty" of all friends of Middle East peace in the United States to come forward with their suggestions, ideas and views.