The United States yesterday launched a last-ditch bid for resumption of the Palestinian autonomy negotiations, but U.S. officials conceded there is little hope of reviving the faltering peace process before the end of the year.

Despite this gloomy outlook, the administration announced that President Carter's special Mideast envoy, Sol M. Linowitz, will leave Friday on a mission to persuade Egyptian President anwar Sadat and Israeli Prime Minister Menachem Begin that it is important to get the talks going again without a long delay.

However, even the normally optimistic Linowitz said: "Realistically, I recognize it will be extraordinarily difficult to get the negotiations resumed at this time."

U.S. officials, elaborating on his remark, said Linowitz does not think he can persuade Sadat, who halted the talks out of anger at Israeli moves in Jerusalem and the occupied West Bank, to abandon his recent call for holding off the negotiations until a new three-way summit conference can be arranged after the U.S. presidential election.

Sadat's move reflects the Egyptian assessment that little can be accomplished until Carter is either reelected -- and thus freed from the need for Jewish electoral support -- or replaced by Ronald Reagan, who theoretically could make a fresh start at tackling the thorny Palestinian negotiations.

If Sadat remains unyielding, the result will be a lengthy and potentially very embarrassing delay in the progress of what Carter has considered his greatest foreign policy achievement -- the process that, beginning with the 1978 Camp David summit, produced the Egyptian Israeli peace treaty and that now is supposed to bring about limited self-government for the Palestinian inhibitants of the Israili-occupied West Bank and Gaza Strip. p

Now that the autonomy talks have dragged on for 15 months with frequent delays and no progress toward an accord, the leadership role that Carter had staked out as a Mideast peacemaker has become increasingly vulnerable to challenge from Arab states hostile to the Camp David process and from West European governments calling for a new approach.

As a result, the United States has found itself more and more isolated in its efforts to maintain the Camp David formula as the main diplomatic channel toward resolving the Arab-Israeli conflict, U.S. officials, sensing this isolation, have become increasingly fearful that a long delay in the autonomy talks could cause the international community to lose all patience with U.S. policy and turn toward other solutions that Washington regards as unacceptable.

The frustration and apprehension that this is causing in administration policymaking circles were brought to the surface last week when Secretary of State Edmund S. Muskie went to the United Nations to announce that the United States would abstain on a Security Council resolution criticizing Israeli policy toward Jerusalem.

In remarks aimed both at the Arab world and America's European allies, Muskie charged that the United National has become "the focus of attempts not to advance the cause of peace, but to restrain it." He added that the recent spate of U.N. resolutions on the Middle East "has neither aided the camp David process nor offered a single alternative with the slightest chance of success."

His bitter tone was widely regarded as a sign that the administration fears it is losing its grasp on the Middle East situation and is unable to find a way of steering events in that region away from renewed tensions and violence.

Although no one will say so publicly, it is no secret that U.S. policymakers privately place most of the blame for this situation on what they regard as the Begin government's recalcitrance, clinging to hard line bargaining positions and talking gratuitous actions that have inflamed Arab world opinion.

Of particular concern to U.S. officials are the Israeli actions that goaded Sadat into halting the autonomy talks -- the continued building of Jewish settlements on the West Bank and a recent Israeli law asserting that Jerusalem, including the Arab eastern sector captured from Jordan in 1967, a Israel's permanent capital.

Although these moves have greatly roded international support for Israel, and for U.S. Mideast policy initiatives, Begin has reaffirmed his refusal to change either stand. And, although U.S. officials said yesterday that part of Linowitz's mission involves trying to persuade Begin to make some conciliatory gesture toward Sadat, they conceded that the Israeli leader is expected to remain unyielding.

In fact, there is a growing feeling in U.S. official circles that any real progress toward an autonomy accord might have to wait not on the November U.S. presidential election, but on the hope that Begin's coalition government will be toppled in the months ahead.

According to this view, even if Linowitz does pull off some feat of resuscitation that gets the comatose talks stirring again, the result is likely to be not real progress but only the illusion of movement. U.S. officials note that Begin, politically beleagured within Israel, has lost all his moderate support and can maintain his power only by playing to factions favoring a hard line on Jerusalem and the occupied territories.

Still, the administration fears that putting the talks on hold indefinitely in hopes that Begin eventually will give way to someone more flexible raises to great a danger that the Camp David process will be swept aside by other initiatives, such as calls for bringing the Palestine Liberation Organization into the peace negotiations.

For that reason, Linowitz is being dispatched for one last shot at trying to convince Begin to be more reasonable, to argue to Sadat that the time for a new summit is not yet ripe, and that the interests of all parties lie in getting back around the negotiating table. But, given the seemingly irreconcilable differences, the expectation is that Linowitz will only be going through the motions and that Carter's Mideast policy is headed for a long period in diplomatic limbo.