President Reagan's objectives in the first summit meeting with a Soviet leader in Washington in 14 years center on negotiating deep cuts in strategic nuclear warheads while prodding the Soviets to get out of Afghanistan and cooperate in the Persian Gulf, administration officials said in a pre-summit news conference yesterday.

In addition, Reagan told the nation in his weekly radio address, he and Soviet leader Mikhail Gorbachev will "celebrate a joint achievement" by signing the intermediate-range nuclear forces (INF) treaty, which requires the destruction of more nuclear weapons under more intrusive means of inspection and control than any pact since the dawn of the atomic age.

"It represents a good bargain," Reagan said of the treaty, which U.S. officials say will bring the dismantling of 859 medium- and shorter-range U.S. missiles and 1,941 comparable Soviet missiles, many carrying three warheads each.

On the eve of today's rally on the Mall to support Soviet Jewry, which is expected to draw tens of thousands of marchers, Reagan also declared in his radio address that Soviet "political, religious and economic oppression remains a solemn concern of the United States" and that "I will raise human rights forcefully" during the meetings with Gorbachev.

A senior U.S. official who has had extensive contact with the advance team of Soviet diplomats said the indications are that Gorbachev will land here Monday afternoon "with a desire to do a lot of things" in his five meetings with Reagan and the numerous contacts planned for him with leaders in American business, science, academia and the press during his 75 hours in Washington.

A major unknown element, the official said, is the impact on Gorbachev's performance here of the internal political jockeying that was dramatized by the recent ouster of Moscow Communist Party chief Boris Yeltsin. A U.S. government expert on Soviet affairs said it appears the Kremlin rumblings are likely to make success in the Washington summit more important to Gorbachev. Any outcome that looks like a failure, as was the case last October in Gorbachev's Reykjavik summit with Reagan, could pose serious risk to his position, the official said.

The meetings of the 56-year-old Soviet leader, who will be making his first trip to the United States amid intense international scrutiny, and the 76-year-old U.S. president, nearing the final year of his eight-year term, will begin with a full-scale ceremonial welcome on the White House South Lawn Tuesday morning. In addition to a working summit meeting, this is to be a state visit with the panoply of official honors, including a White House state dinner.

Gorbachev, accompanied by his wife, Raisa, is scheduled to land in a special Soviet airliner at 4:40 p.m. Monday at Andrews Air Force Base, but to have no official meetings before pulling up to the White House in an armored Soviet Zil limousine at 10 a.m. Tuesday.

The INF treaty signing is scheduled in the East Room Tuesday afternoon as the symbolic and substantive prelude to extensive discussions of an arms treaty aiming at 50 percent reductions in the two nations' vast strategic arsenals of intercontinental ballistic missiles, missile-carrying submarines and warplanes carrying nuclear bombs.

Joint briefings twice daily by White House spokesman Marlin Fitzwater and Soviet Foreign Ministry spokesman Gennadi Gerasimov, an innovative feature of the summit, will describe the general topics under discussion in each of the substantive meetings Tuesday, Wednesday and Thursday. However, in a briefing yesterday for journalists in the capital to cover the summit, Fitzwater said that, in keeping with the practice at the Reagan-Gorbachev meetings at Geneva in November 1985 and Reykjavik last October, "we will not discuss the conclusions and content of the various meetings until the summit is completed." Press facilities will be in the Commerce Department and the grand ballroom of the J.W. Marriott Hotel.

After the final meeting with Reagan at 2 p.m. Thursday, Gorbachev is scheduled to leave the White House, hold a news conference at the Soviet Embassy complex on Wisconsin Avenue at 5:30 p.m., and depart the United States at 8 p.m. Despite several hints from Moscow that Gorbachev might decide at the last minute to stay longer, U.S. officials said they have no indication of a Soviet desire to extend the meetings beyond Thursday.

Rozanne L. Ridgway, assistant secretary of state for European and Canadian affairs, opened a discussion of the summit agenda at the Commerce Department joint press facility by stating the official U.S. objectives: "Overall, to provide a further impetus to the {U.S.-Soviet} process already in place and to keep the Soviet Union moving in the right direction.

"Specifically, to sign the INF treaty and to push ahead on the whole substantive agenda -- lasting improvement in Soviet human rights practices, peaceful settlement of regional conflicts, a broadening of the dialogue between our governments and peoples and strengthening of U.S. and allied security through stabilizing and effectively verifiable arms reductions."

In addition, Ridgway said, "We hope General Secretary Gorbachev acquires a better understanding of how Americans think and how our system works." She added that Reagan "going into the summit is well prepared and ready for serious discussion and our contacts with the Soviet side suggest that Mr. Gorbachev is ready for the same."

Fitzwater said Reagan is spending the weekend at the White House with a two-inch-thick briefing book on all aspects of the meetings with Gorbachev. The policies and plans in the book, Fitzwater said, flowed out of daily discussions this week between Reagan and his new national security adviser, Lt. Gen. Colin L. Powell, two private meetings of Reagan with Secretary of State George P. Shultz during the week and two meetings of the inner circle of the National Security Council.

A major part of the White House discussion concerned the length of time the two sides might agree not to withdraw from the 1972 Antiballistic Missile (ABM) Treaty, according to an administration official. Shultz has described this as important to the stability and predictability both sides say they seek. Currently, the United States backs a seven-year nonwithdrawal period; the Soviets want a 10-year adherence.

Guarded comments by official sources indicate that U.S. compromise positions, to be tendered if Soviet compromise offers seem to warrant them, were discussed on the nonwithdrawal period and other issues. Though a consensus on possible U.S. fallback offers may have been approached -- some officials left the meeting believing that choices had been made -- a White House official said emphatically that Reagan had made no decisions at the session.

On a related issue, H. Allen Holmes, assistant secretary of state for politico-military affairs, refused to say yesterday how the United States would respond to a possible Soviet willingness to move ahead with strategic arms cutbacks without resolving the differing U.S. and Soviet interpretations of the ABM pact. On Friday, Soviet spokesman Gerasimov suggested this possibility, which would be a major change in the Soviet position.

Holmes, at the pre-summit news conference, said the U.S. side would respond to this Soviet shift only if it is offered officially and "we see the fine print."

The State Department arms control official said that in the strategic arms bargaining, "our principal objective at this meeting will be to get the required sublimits to make this a stable reduction program."

Holmes said the U.S.-proposed "sublimit," or special ceiling on specific types of weaponry, that the administration is concentrating on is the one limiting all strategic intercontinental ballistic warheads, land-based or submarine-based, to 4,800. The Soviets countered during Shultz's trip to Geneva two weeks ago by informally discussing a possible 5,100-warhead limit in this category.

"We have also wanted to get" an additional sublimit on land-based intercontinental ballistic missile warheads, said Holmes, speaking of a separate 3,300-warhead limit that the administration is reportedly ready to drop in return for Soviet concessions. White House sources said no formal decision to drop this requirement was made at the meeting Friday, and several officials expressed anger at outgoing Arms Control and Disarmament Agency Director Kenneth L. Adelman for saying publicly Thursday that "I'm not convinced it's essential" that the 3,300-warhead limit be retained. Adelman also noted at the time that such a limit might be obtainable if the United States persisted because the Soviets have offered a similar number.

Regarding the regional issues, Undersecretary of State Michael H. Armacost said, "We'd like to see Soviet troops move out of Afghanistan in 1988" and that Gorbachev will be asked to establish a specific and early withdrawal timetable.

On the Persian Gulf, Armacost reported indications that Moscow may be ready after more than two months' delay to discuss passage of a U.N.-sanctioned arms embargo against Iran due to Tehran's refusal to accept a cease-fire and withdrawal ordered by the U.N. Security Council. Gorbachev is likely to be pressed on this issue, Armacost indicated.