U.S. Secretary of State Cyrus R. Vance has accepted an invitation to attend the start of the next round of Egyptian-Israeli peace talks scheduled here Jan. 15, an Israeli spokesman said today.

Vance's acceptance was conveyed to Israeli Foreign Minister Moshe Dayan by U.S. Ambassador Samuel W. Lewis during an hour-and-a-half meeting today in Tel Aviv.

It is presumed that the two discussed the arrangements and agenda for the opening of negotiations by the Egyptian-Israeli political committee.

Dayan told an Israeli television interviewer tonight that he expects that Egypt will come to the meeting with a counterproposal completely different from the plan Israel has submitted. He added that he expects Egypt's proposals to be open for Israeli counter-offers, too.

Dayan said that there have been no substantive differences between himself and Prime Minister Menahem Begin, that there are no longer any differences in analysis of the negotiating situation, but that, unlike Begin, he is "not such a happy man." The negotiations so far, said Dayan, have not been "a picnic for me. It was a road of pain for me."

Since there are no longer any Israeli representatives in Cairo, the Americans are understood to be acting as the main conduit for the exchange of views between the Egyptian and Israeli governments.

The main task of the political committee is to reconcile the positions of Israel and Egypt on the political future of the Israeli-occupied West Bank. The Israelis say, however, that they recognize that they cannot negotiate for very long or in very much depth with Egypt over a territory where the Egyptians have no legal authority and no claims.

As one Israeli official put it. "Sadat's real problem . . . is getting a negotiating partner for Israel on the West Bank or deciding to drop the is-can negotiate about," meaning the Is-negotiating partner for Israel on the

The forum for negotiating most of the problems in the Sinai is the second committee Begin and Sadat set up when they met in Ismailia last week. No date has been announced for that unit, the military committee, to start its work. It is to meet in Cairo under he two countries' defense ministers and have only Israeli and Egyptian delegates.

The political committee will include the United States and the United Nations.

Israeli and American officials concede that the choice of Jerusalem as the place to discuss the West Bank indicates that neither Begin nor sadat expect that Jordan, the logical negotiator for that territory, can be expected to join in the talks for two to three months.

While Sadat has in effect recognized Jerusalem as Israel's capital by addressing the Israeli Parliament here, Jordan's King Hussein has yet to give public endorsement to any of Egypt's steps towards recognition of Israel.

Therefore, it is, thought unlikely that, as his first move Hussein would agree to send representatives to Jerusalem, a city where he claims sovereignty over the Arab quarters.

Israeli and Egyptian leaders have predicted that the political committee will work for two to three months. There is always the possibility that the real negotiations could be taken out of that forum and transferred elsewhere.

Despite all the mounting pressure on King Hussein - from the United States, Egypt and Israel - to join in the talks, the Israelis seem content to talk to the Egyptians alone for the time being.

This approach seems to be based in part on a number of hints and comments the Israelis say Sadat hadropped in his private conversations with Israeli leaders. These comments have convinced the Israelis that, although Sadat must for the time being continue to go through a certain number of motions for public consumption, he is no more interested than Israel, Jordan or the United States in seeing the establishment of a potentially radical new Palestinian state in the Middle East.

The Israelis say they also detect private flexibility behind Sadat's public opposition to any Israeli troops remaining on the West Bank or in the Sinai.

For these reasons, the Israelis say they are convinced that President Carter's public restatements of Washington's opposition to establishment of a Palestinian state need not complicate matters, Sadat's remarks to the contrary notwithstanding.

There is also apparently more give in Israeli positions than the public statements would indicate.

The hardest Israeli position was expressed by Dayan in Parliament on Wednesday. He said that the provision Israel has offered of review after five years of the West Bank autonomy arrangements does not mean that it could be ended and replaced by something else after five years.

"We are proposing," he said, that they have absolute authority "that . . . they will run their lives as they wish. . . . But we are not proposing over the territory or over the Jews who reside there."

The Israeli army, he said, will guarantee that Jews can buy land on the West Bank and that large numbers of Palestinians do not return from the refugee camps of Lebanon.

"We do not want foreigners to protect us, but neither do we want to live as foreigners in our own homeland," he said of the West Bank.

Other cabinet ministers said, however, that the five-year review proposal was meant to make the stationing of Israeli forces on the West Bank palatable, offering the Palestinians and Jordan the possibility that the troops would eventually leave.

Even Dayan started backtracking immediately. His spokesmen said that Dayan regretted choosing the example of land sales to Jews as a proper subject for military action. On television tonight he said that he had not meant to suggest that the Israeli army would serve as the first resort in case of a violation of the agreement.