Jordan's King Hussein told an audience of local leaders in Amman Monday that he has a letter from President Reagan committing the United States to put pressure on Israel to restore Arab rights in its occupied territories.

"The United States is determined that land and rights should be given back to their owners, and is ready to use its weight in this respect," Hussein was quoted as saying in a Manchester Guardian dispatch from the Jordanian capital.

Hussein said that although the United States hoped Jerusalem would remain undivided, Reagan "nevertheless recognized Arab rights concerning Jerusalem and the rest of the occupied territories."

State Department and White House officials refused to confirm that Reagan had sent a letter to Hussein.

The king, who met with Reagan in Washington just before Christmas, briefed Jordanian political and business leaders after three days of talks with Palestine Liberation Organization chairman Yasser Arafat, who arrived in Moscow yesterday from Amman. The king's briefing was private, but Jordanian officials later issued an official version of Hussein's remarks, his first extensive public comments since his return from Washington.

According to this statement, Hussein said that he believes time is running out for a negotiated solution. The king told his audience that early March was the deadline for a concerted Arab approach. After then, he said, American attention would be diverted, and the opportunity for peace could be lost.

In another development yesterday, Moroccan officials announced that an Arab League mission would visit London Feb. 7, ending a diplomatic impasse that followed Prime Minister Margaret Thatcher's refusal to receive any PLO official. A compromise was arranged in which the PLO will be represented on the mission by Mohammed Milhem, an exiled West Bank mayor who is not a member of the PLO executive committee.

Hussein said the United States was willing to consider an Arab proposal to shorten a proposed transitional period between free elections in the occupied territories and full autonomy. Both the Camp David accords between Israel and Egypt and Reagan's Sept. 1 peace plan set the interval at five years.

Washington Post staff writer John M. Goshko reported:

In private, administration officials said that U.S. policy toward the occupied territories remains unchanged from the positions spelled out by Reagan in his Sept. 1 speech.

Although the officials said they did not know what Hussein meant by his reported reference to "Arab rights" in the occupied territories, they noted that the basis of the U.S. proposals is the call for the West Bank and Gaza Strip eventually to gain autonomy "in association with Jordan."

The officials said U.S. policy on Jerusalem continues to be that the city should remain undivided and that its ultimate status should be determined through negotiation. They also called attention to the so-called "talking points" that were not mentioned by Reagan on Sept. 1 but that were communicated at that time to Hussein and the leaders of Israel, Egypt and Saudi Arabia by the U.S. ambassadors in those countries.

These points spelled out specific positions that the United States intends to support in any future negotiations about the occupied territories. Among other things, they state specifically that the United States favors Palestinian inhabitants of East Jerusalem having the right to vote for the self-governing authority envisioned for the West Bank and Gaza under the Camp David proposals for an interim period of Palestinian self-rule in these areas.

In the talking points, the United States also said it would support the right of the self-governing authority to have basic control over land and water resources and internal security in the occupied territories. In past negotiations on an autonomy agreement, Israel has opposed giving those rights and powers to the Palestinians.