Prime Minister Mustapha Khalil said tonight that the signing of a peace treaty between Egypt and Israel now appears to be imminent.

He said it was his "understanding" that the Israeli Cabinet in principle has agreed to proposals acceptable to Egypt on the remaining points at issue. He also said it was his "personal assessment" that President Carter would not be coming here this week if agreement were not at hand.

Khalil, reached by telephone after the surprise announcement of Carter's visit, stressed that he had only "unofficial" information about the outcome of today's debate in the Israeli Cabinet.

There has been no official announcement about exactly what Carter proposed Sunday night or what the Israelis accepted, and Khalil was reluctant to go beyond what has been said publicly. But when he was asked whether Carter's agreement meant a treaty was now set, he replied, "I agree with your analysis."

Khalil did not say how it was possible that the Israelis, who have resolutely and totally refused to accept the Egyptian view on these issues, even when it was generally supported by the Americans, could suddenly have accepted a formula agreeable to the Egyptians.

He said, laughing, that "ideas come and go in negotiations and I don't like to use the term concessions." He said it was "correct" that Egypt has not changed its position at all or deviated from the stand it took on these issues at the Camp David negotiations last week.

The word of Khalil can be considered authoritative: he is foreign minister as well as prime minister, was Egypt's chief negotiator in the unsuccessful Camp David talks last month and he met with President Anwar Sadat and U.S. Ambassador Hermann Eilts this morning.

"My information, which is unofficial," he said, "is that the Israelis have accpeted interpretive notes on articles 4 and 6 and an exchange of letters among Israel, Egypt and the United States on the linkage issue. It seems that they have accpeted this in principle."

Those are shorthand designations for the only remaining issues blocking conclusion of a peace treaty. Egypt has been insisting on "interpretive notes" redefining two articles of the draft peace treaty worked out in Washington megotiations last year, one dealing with security arrangements in the Sinai, the other with the relative weight of Egypt's obligations under the treaty to Israel and to other Arab states with which it has defense commitments.

"Linkage" has been an even more intractable issue. It refers to Egypt's attempt to tie the implementation of full peaceful relations between Egypt and Israel to implementation of Palestinian autonomy in the West Bank and the Gaza Strip.

Leaving no doubt about his assessment of the situation, Khalil told several Western journalists who telephoned him that "the fact that the Israeli Cabinet has accepted the linkage issue and the interpretive notes and that Carter is coming himself is a very positive sign."

He said that the Egyptians "are very glad to receive a personal visit from Mr. Carter. He will be welcomed with the appropriate honors he deserves for his courage, his time and his effort. He will receive a wholehearted welcome from the government and the people."

Carter's only previous visit to Egypt as president consisted of a few hours with Sadat at Aswan airport in January 1977, while Carter was on his way from Saudi Arabia to Europe. This tiem the visit is expected to take place in Cairo and Egypt is likely to organize a tumultuous popular reception.

Khalil's optimism and the news of Carter's visit represent an almost complete transtormation of the atmosphere here in little more than 24 hours. Khalil said Carter was coming because of "significant developments," but only yesterday it seemed unlikely that any significant developments in negotiations were possible any time soon.

Khalil said tonight that the news of Carter's trip was "not a surprise," but he had said nothing about it when he briefed the press after his meeting with Sadat and Eilts this morning.

That press briefing substituted for a press conference Sadat had scheduled in which he was widely expected to consign the negotiations to the deep freeze, if not to a grave.

Sadat had promised the press he would have "lots" to say in the wake of reports from Washington that Carter and Begin had gotten nowhere in their difficult negotiations over the remaining issues. But that was before Carter's move later Sunday to submit to Begin new proposals that set in motion a chain of rapid developments.

The very fact of the postponement of the press conferencxe indicated that the resignation and bitterness about Begin that prevailed on Sunday, marked by scathing attacks in the press on the Israeli leader's conduct, had been supplanted by anticipation.