Prime Minister Menachem Begin indicated today that Israel would not press its selfproclaimed right to launch new settlements in the occupied West Bank when the Dec. 17 deadline passes.

Jerusalem's earlier threats to move in new groups of settlers had endangered the tortuous peace negotiations with Egypt and brought a stern denunciation from President Carter.

At a news conference here today, Begin refused to commit himself or his government to a future course of action and several times insisted on "our right" to establish further Jewish colonies on the Jordan River's West Bank captured by Israel in 1967.

But then he added that "there are political questions to consider." This was taken to mean that Begin realizes that further Israeli moves would jeopardize the still unsigned peace treaty.

Representatives of Egyptian President Anwar Sadat had expressed deep concern over a warning last week by an Israeli cabinet minister that Israel would start fresh settlements when the Dec. 17 "deadline" passed. The warning, however, came from Arik Sharon, the agriculture minister and a hardline supporter of the settlements.

Begin repeatedly asserted today that any decision was up to Israel's full Cabinet. But his emphasis on the political dangers of any new West Bank move was the highest public expression that Israel is alive to the risk of such a course.

Begin and Sadat's special representative, Sayed Marei, were in Oslo to collect the Nobel Peace Prize both leaders were awarded on Sunday.

The significance of Dec. 17 flows from the Comp David meeting where Begin and Sadat agreed on a "framework" for peace. That accord, reached on Sept. 17, forecast three months to negotiate a peace treaty.

Although Egyptian and Israeli diplomats drew up a draft accord in November, Cairo has balked at some of its provisions. Israel claims that the Camp David pact prevented further West Bank settlements only until the three months had passed. But this view is strongly disputed by Carter, the Camp David host, and Sadat. For the time being, at least, the issue appears to be academic.

Begin also made clear that the three month deadline is now more of a hope than a reality.

"We are prepared to extend it if necessary," he said. "If it is not reached, let us do whatever we can to reach that goal and sign that peace treaty." He added, "Patience doesn't have a date."

Marei said in an interview that Egypt too expected the bargaining to continue after Dec. 17.

"The negotiations are going on and must go on," he said. "But the time element is a factor which is important."

The Israeli prime minister, talking with reporters while his beaming wife looked on, sounded far more conciliatory than he did in his formal speech accepting the prize on Sunday.

Up to now, he and other Israelis have been suggesting that Cairo was virtually bound to sign the draft treaty worked out in Washington last month. Today Begin acknowledged that Sadat's "central government" has the right to decide "whether to change the draft prepared by the negotiators."

Israel likes the draft as it stands, but Sadat wants several amendments.

Begin indicated that he is in a bargaining modd, saying, "in my heart I believe the peace treaty will be signed."

He left here this afternoon for Jerusalem where he is to see Secretary of State Cyrus Vance on Tuesday. Vance, trying to bridge the gap between Egypt and Israel, comes to Jerusalem from a meeting with Sadat in Cairo.

Earlier today Begin met with Norwegian Prime Minister Odvar Nordli and Foreign Minister Knut Frydenlund. They pressed him to use Israel's arms and other influence with the Christian militia in southern Lebanon.The Christians have been firing at Norwegian soldiers there as part of a United Nations peace force, and hampering their movements.

Begin said his talks with the Norwegians were "very good... very satisfactory." Oslo's officials declined to characterize them.