The Israeli cabinet, in a clear snub of Defense Minister Ezer Weizman, put off yesterday for a week discussion of new peace proposals Egyptian President Anwar Sadat suggested to Weizman in a meeting in Austria last week.

The decision, coupled with sharp criticism of Weizman and a cabinet decree barring such independent diplomatic activities in the future, showed Prime Minister Menachem Begin's government to be in some disunity as Israel, Egypt and the United States prepare to hold peace talks in Britain tomorrow.

The contents of Sadat's latest proposal have not been released by the Israeli government but the Egyptian leader, in an interview published yesterday in the Jerusalem Post, indicated Egypt has softened its position at least in two areas.

The interviewer, David Landau, said Sadat hinted that he was willing to accept the presence of Israeli forces in a limited strategic role on the West Bank after a peace agreement and suggested that Israel could continue to have some standing in administration of the West Bank.

Egypt's official position has called for complete Israeli military withdrawal from occupied territories and Arab rule of the West Bank with no Israeli role.

The Israeli cabinet's actions reportedly were accompanied by fierce internal bickering among the ministers and by growing irritation by Begin over Sadat's preference for talking with Israelis other than himself or Foreign Minister Moshe Dayan.

The cabinet shut the door on future Weizman talks with Sadat by ruling that negotiating representatives of Egypt and Israel should, in the future, be "reciprocal" in rank.

Even more explicitly, the cabinet snubbed opposition leader Shimon Peres' negotiating efforts. Peres twice has met with Sadat, most recently in Vienna this month. Yesterday. Begin's cabinet declared that the exclusive authority for conducting negotiations with Egypt "or with any state in a state of war with Israel" rests with the government and its authorized representatives.

Government sources said Weizman was sharply criticized by several cabinet members, particularly Industry and Commerce Minister Yigael Hurvitz and Agricultural Minister Ariel Sharon.

The defense minister was said afterward to have characterized their attitude as showing "jealously and narrow-mindness," and reportedly displayed his anger later at a meeting of the parliament's foreign affairs and security committee.

Following the cabinet meeting, Begin told reporters that Weizman's conversations with Sadat came up but that the ministers did not debate them at length because of a tight schedule. The cabinet however, did, debate briefly the foreign ministers' conference in Britain which will be attended by Dayan, Egyptian Foreign Minister Mohammed Ibralim Kamel and Secretary of State Cyrus Vance.

In a speech last night to the Herut faction of his Likud coalition, Begin referred to criticism of his foreign policy in saying: "The leaders of Egypt do not cease defaming me. This time, unlike my habit, I shall turn a deaf ear.

"In the world, a campaign is being waged for my resignation. I am being termed an obstacle to peace. To my mind, I am indeed an obstacle.An obstacle against capitulation. Together with my colleagues in the government, the Knesset, the faction and the movement," he said.

In his only reference to Weizman, Begin said he had received the Sadat proposals and added: "We shall discuss them at next week's cabinet session."

While Weizman and other officials are known to consider Sadat's suggestions a softening of the Egyptian negotiating stance, sources in the government said that Begin believes the Egyptian president is cleverly manipulating world opinion in his own favor and is portraying Israel as intransigent over any territorial concessions in the West Bank and Gaza Strip.

In his interview with the Jerusalem Post, Sadat pointedly spoke of his "special relationship" with Weizman and said he could "speak the same language" with both Weizman and Peres. But he referred to Begin as "hardline" and said he had no common language with him.

After an invitation was extended by Egyptian War Minister Mohammed Gamassy, Sadat reportedly also reiterated that Israel must withdraw from most of the West Bank but that some border adjustments could be made for security.

In explaining the cabinet's decision to require reciprocal ministerial stature of Egyptian and Israeli negotiators, Cabinet Secretary Aryeh Naor said: "It is inconceivable that, for example, our foreign minister would invite . . . the Egyptian ambassador to the United Nations without first speaking about this with the foreign minister."

Israel Cabinet Secretary Aeyeh Naor stressed that any cabinet minister must have the government's permission to travel to another country, an apparent reference to a reported Sadat invitation to Weizman to continue the peace dialogue they held in Salzburg, Austria, in Alexandria, Egypt, after the foreign ministers' conference in Britain.

The foreign ministers' conference was to have been held at the Churchill Hotel in London but for security reasons it reportedly has been switched to the 1,000-year-old Leeds Castle, which is situated in a lake and is considered secure from possible terrorist attack. The Churchill is only a few minutes walk from the sites of recent terrorist killings in London.

Naor confirmed that the cabinet discussed "in a general way" reports from Cairo that Israeli Labor Party leaders, including Peres, would meet later this summer with Egyptian leaders at an undisclosed site in Egypt.

Sadat, according to Egyptian sources, extended an invitation to Pres when the two met in Vienna during a conference of the Socialist International. Out of that meeting came a peace program drafted by Australian Chanceller Bruno Kreisky and West German Socialist leader Willy Brandt.

The Kreisky-Brandt plan calls for secure borders on the West Bank and Gaza in accordance with U.N. Resolution 242 and the recognition of the right of Palestinian Arabs to participaee in the determination of their own future. In many respects, it is similar to the "Aswan formula" approved by President Carter Jan. 4.

When asked about Pres' reported plans to take Labor Party officials to Egypt for peace talks, Naor said: "The significance is that if any invitation reaches the Labor Party . . . it (the party) will have to apply to the government and request permission."

He said the Cabinet felt it was necessary to issue a statement about the "level of representation" of negotiating figures "because in the last few days reports were published in the name of the president of Egypt, which were not denied, that he is not willing to maintain a link or have any contact whatsover with the prime minister. The government believes that the people of Israel did not give to the president of Egypt the authority to determine who will represent the state of Israel."