President Reagan yesterday praised visiting Egyptian President Hosni Mubarak's recent proposal for renewed Arab-Israeli negotiations as a "positive contribution" but gave no indication that the United States was ready to take more than "an active interest" in helping to revive the deadlocked Middle East peace process.

In remarks made after a White House luncheon given in Mubarak's honor, Reagan said he was encouraged by the "positive trends" in the area and had assured his guest of "my personal commitment" to work with Egypt for a lasting peace in that troubled region.

He noted, however, that "the parties are still a long way from the negotiating table," and indicated that U.S. support would be limited for now to helping Egypt and others interested in reviving the peace process to find a mutually acceptable formula based on U.N. Security Council Resolution 242.

Altogether, Mubarak appeared to have fallen short in his quest to arouse a new American activism in the Middle East peace process. At the 2 1/2-hour meeting and luncheon with the president, he was questioned closely on his plan for a three-stage negotiating process starting with "discussions" between a joint Jordanian-Palestinian delegation and the United States but left with no American commitment to his approach.

Mubarak also got no U.S. commitment on an Egyptian request for nearly $1.9 billion in additional aid over the next two years.

A senior administration official, briefing reporters after Mubarak's departure from the White House, said the Egyptian leader had been given "no assurances" regarding his request for $870 million in supplementary economic assistance this fiscal year.

Later, Mubarak was warned on Capitol Hill, where he met with House members and Senate Foreign Relations Committee members, that his request for more aid faced "tough sledding" unless Egypt returned its ambassador to Israel. Mubarak was handed a letter signed by 98 members of Congress requesting the envoy's return as well as an overall improvement in Egyptian-Israeli relations.

To the embarrassment of both presidents, the noontime luncheon took place just as the United States was casting the sole veto in the U.N. Security Council on a resolution condemning Israel for its raids on villages in southern Lebanon and alleged mistreatment of inhabitants there. As expected, Egypt voted in favor of the resolution.

Neither president brought up the issue in their prepared White House statements and both seemed eager to emphasize the positive side of their meeting, which Mubarak called "most constructive and rewarding."

"I am pleased to note that we agree together on the centrality of the Palestinian question to the situation in the Middle East," Mubarak said. "It is the key to progress and the source of despair and tension."

The Egyptian leader carefully avoided raising once again the controversial issue of U.S. recognition of the Palestine Liberation Organization. During his last visit here in February 1982, Mubarak greatly irritated the administration by publicly urging Reagan to his face to open "a direct dialogue" with the PLO and drop the longstanding U.S. preconditions that the Palestinian organization first accept U.N. Resolution 242.The resolution calls upon Israel to relinquish occupied Arab lands in return for peace and secure borders, and calls on the Arabs to renounce terrorism and recognize Israel.

This time, Mubarak spoke only of Palestinian "self-determination," saying he thought "no nation is more qualified than America to support" this right.

"I also believe that no leader is more equipped to play an historic role and fulfill a sacred mission in the Middle East," he added.

The senior administration official briefing reporters made it clear, however, that the United States wanted answers to a lot more questions about Mubarak's proposal for a three-step approach to new Middle East peace talks before it would reengage itself fully in the process.

The focus of these questions, he said, was on what precisely Egypt had in mind by proposing separate talks initially between Washington and a Jordanian-Palestinian delegation without Israel and how this step would lead to direct Arab-Israeli negotiations, which remain the administration's goal.

He said the discussions between Reagan and Mubarak consisted of a process in which each Egyptian answer "led to another question" by the United States. "It was an unending process," he said.

Asked specifically whether the United States was ready to hold talks with a Jordanian-Palestinian delegation without PLO members, he replied, "There is no answer to that."