President Reagan honored Ambassador Philip C. Habib in an emotional White House ceremony yesterday, and both men used the occasion to promote the administration's peace initiative in the Middle East.

Administration officials said that Reagan today is likely to ask Habib, after a rest, to undertake further missions in pursuit of the peace plan, which Reagan unveiled last week and which has been rejected by the Israeli government.

A State Department spokesman said yesterday that the administration does not regard Israel's rejection of the initiative as final and intends to apply "proper pressure" in the form of persuasion to get Israel and the Arab states to the negotiating table.

Reagan ended his California vacation yesterday by flying back for the East Room ceremony, which was attended by virtually the entire Cabinet and several political figures from past administrations.

Awarding Habib the Medal of Freedom, Reagan said his efforts to secure the cease-fire in Lebanon had saved "thousands of innocent lives" in Beirut and "brought us one step closer to a peaceful resolution to the Arab-Israeli conflict."

Habib responded by thanking Reagan for backing his efforts and for giving the U.S. diplomatic team the "leeway" to negotiate. After saying that the Middle East peace is "tenuous" and that there is still much to be accomplished, Habib said of the peace process, "I'm a chronic optimist, Mr. President, and I'm convinced that it's going to stay on track, and it's going to stay on track partly because of the initiative you most recently took with respect to peace in the Middle East."

Earlier, State Department spokesman John Hughes rejected the position of Israeli leaders that talks on autonomy for the Palestinian inhabitants of the West Bank and the Gaza Strip should be postponed for several months until the Lebanon situation is settled.

Hughes said the U.S. view is that "the talks should go forward without direct relationship to the events in Lebanon" and that they require new elements like Reagan's initiative to "enhance the prospects" for a successful autonomy agreement.

Discussing Israeli resistance to the Reagan plan, Hughes said, "The president is very serious and determined about this initiative, and that seriousness and determination is not diluted by the Israeli response . . . . Diplomatic exchanges are constantly going on, and ways are being devised to apply proper pressure" on Israel and the other parties.

Asked what "proper pressure" meant, Hughes replied that Secretary of State George P. Shultz, in his interview on the CBS program "Face the Nation" Sunday, made "very clear" that this pressure does not include the withholding of U.S. military aid to Israel.

"By proper pressure we mean persuasiveness about peace and security in the area," Hughes said. "Nobody expected this would be an easy road. Nobody expected it would be wrapped up in 24 hours. We are going to need hard and earnest negotiations. I guess we may have to to have negotiations to bring about negotiations."

Later, he defined the phrase further as pressure "of the most ethical and principled kind, namely persuasion and drawing attention to peace and security" for Israel.

Meanwhile in London, Secretary of Defense Caspar W. Weinberger said that the president's initiative had won "a fine reception" in the Middle East outside of Israel. And even in Israel, he said, "there is a significant amount of support" for the president's call to halt the expansion of Israeli settlements on the West Bank. Israeli responded to Reagan's message by approving three additional settlements.

In the East Room ceremony, Reagan said Habib had earned "worldwide admiration" for his efforts in securing peace in Lebanon.

"His successful negotiation of the cease-fire in Lebanon and the resolution of the West Beirut crisis stands out as one of the unique feats of diplomacy in modern times," said the citation presented to Habib, who came out of retirement to undertake the negotiations.

Reagan then departed from his text, walked over to Habib and spoke personally to him, saying Habib deserved "combat pay" for his efforts.

Habib, 62, has had two heart attacks and multiple bypass surgery, and the only question about his involvement in future negotiations, according to administration officials, is whether he believes his health will permit it. Habib is expected to discuss the subject at a White House luncheon with Reagan today.

Habib responded to Reagan's praise by praising his deputy, Maurice Draper, Shultz and the president.

"You honor me very greatly, Mr. President," Habib said. "It's a long way, as I once said, for a boy from Brooklyn, via Idaho, out to California and then here. . . . It's particularly fitting, considering that my mother and father came from Lebanon, that their son had something to do with bringing a bit of peace to their harried land."

Speaking of Reagan's peace initiative, Habib said:

"There is no more worthy cause. There is no subject worthy of greater concern on the part of the United States than the cause of peace in the Middle East. Peace and justice for all the nations in the Middle East is what all of us have striven for for many years, and under your leadership, and that of Secretary Shultz, I would hope that it will be with us very soon."

Reagan seemed on the verge of tears at one point in his remarks praising Habib as representing the best impulses of government service.

"Phil is not alone," Reagan said. "When we honor him, we honor all of you in government service, diplomats, soldiers, analysts and secretaries, who have shown once again your commitment, loyalty and skill."