President Reagan is demanding an Israeli agreement to withdraw from Lebanon before he will settle on a date for his invitation to Prime Minister Menachem Begin to visit Washington, a U.S. official said today.

The Begin visit, which had tentatively been set for mid-February, hinges not just on signs of progress in the troop withdrawal talks with Lebanon but on achieving an agreement, said the official who declined to be identified.

"The president said there is no purpose in meeting if the main subject is going to be squabbling over minor details on Lebanon," the official said, referring to a letter delivered to Begin earlier this month. "He wants not just progress, but an agreement on withdrawal . . . The president doesn't want to spend time hashing out minor details."

A new dispute between Israel and Lebanon about withdrawal of foreign forces from Lebanon has led to cancellation of two scheduled subcommittee meetings of their representatives this week, Israeli officials said today, according to Reuter. Israeli and Lebanese negotiators were unable to agree on a site for the meetings.

The willingness of U.S. officials to confirm the content of the Reagan letter also appeared to signal a deliberate decision by the United States to step up the diplomatic pressure for Israel to reduce its demands in the stalled negotiations with Lebanon.

Asked about published reports that the administration is considering economic and military aid sanctions against Israel, the U.S. official said, "While people are not working in the language of threats, persuasion does not seem to be working."

The official said that although U.S.-Israeli relations have gone through a number of strains since the invasion of Lebanon last June, the situation today is "far more serious than it was before." The two countries, he said, "view the Lebanon negotiations from very different perspectives."

Reagan's position was first outlined to Begin in an earlier letter delivered by U.S. special negotiator Philip C. Habib in mid-January, a letter which Begin aides described as the time as "friendly." The aides said then that the question of the trip to Washington did not even come up in the discussions.

Begin was to have met with Reagan on Nov. 19 during a visit to the United States but the meeting never took place because his trip was cut short by the death of his wife. He then was invited back to Washington for a mid-February presidential meeting.

But in the days since then, it has become increasingly clear that the administration has linked Begin's welcome in Washington to the Lebanon negotiations.

The United States is pressing for a rapid agreement in the troop withdrawal negotiations in order to turn full attention to the president's broader Middle East peace initiative and negotiations on the future of the occupied West Bank and Gaza Strip. The U.S. official said the administration views the next five weeks as "crucial" in seeking progress toward its broader objectives.

By the end of February, Jordan's King Hussein is expected to have made a decision on whether, and under what conditions, he will join in negotiations based on the Reagan plan. The Palestine National Council, the governing body of the Palestine Liberation Organization, is also scheduled to meet in February to decide its attitude toward such negotiations and Hussein's role in them.

There are also expected to be two events in Israel next month that will affect the country's domestic politics and could easily have an impact on the negotiating atmosphere.

One is the release of the report of the Israeli commission that has been investigating the massacre of Palestinian refugees in West Beirut last September. It could set off a major political debate that could lead to early elections here this year.

The other is the expected announcement by Yitzhak Navon, Israel's popular president, on whether he will seek a second term to the largely ceremonial post. Navon is being encouraged by a number of associates to leave the presidency and seek the leadership of the opposition Labor Party in order to challenge the Begin government in the anticipated elections.

The stalemate in the Lebanon negotiations was spotlighted by Habib's last meeting with Begin here Sunday. Habib made a number of attempts to get Israel to soften its demands for creation of a "security zone" in southern Lebanon, but the U.S. official said the Israelis were "very tough" in the meeting and that "no progress" was made.

Israel is insisting that the security zone contain three to five early warning stations manned by Israelis, at least two of which would not be simply electronic listening posts but would amount to small Israeli Army bases within Lebanon's boundaries. The United States has backed Beirut's insistence that Israel's withdrawal from Lebanon be total, suggesting that if early warning stations are established they could be manned by the multinational force now in Beirut, the United Nations force that is stationed in southern Lebanon or the Lebanese Army.

The other major issue in the negotiations centers on Israel's demand for "normal relations" with Lebanon in return for a troop withdrawal. A source close to Begin argued today that Lebanon wants normal relations with Israel but is under pressure from Arab countries not to take the step and needs strong American support to do so.

But the U.S. official said the United States agrees with the official Lebanese position that--given the occupation of its land, the outside Arab pressure and the likely reaction of Lebanon's Moslem majority--it is not realistic to expect normalization under the present circumstances.