UNITED NATIONS, DEC. 7 -- Soviet President Mikhail Gorbachev, condemning the "one-sided reliance on military power" that has shaped the nature of Soviet foreign policy in the past, today announced unilateral cuts of half a million men, including six divisions based in Eastern Europe, in the Soviet armed forces over the next two years.

In an address that departed dramatically from the traditions of Soviet rhetoric before the United Nations General Assembly, Gorbachev repeatedly struck notes of conciliation and hope. He combined this with far more specific and extensive announcements for what he decribed as rapidly changing world conditions.

Gorbachev said the funds saved by reducing military expenditures would be invested in the Soviet Union's troubled civilian economy.

He also signaled a major shift in domestic policy by publicly committing the Soviet Union to improving its human rights record and relaxing travel restrictions that have been sharply criticized in the West.

Gorbachev's one-hour speech to the world body underscored the dramatic transformation in Soviet attitudes that has occurred as a result of his reform program known as perestroika.

The address came hours before Soviet Foreign Minister Eduard Shevardnadze announced that Gorbachev would cut short his visit to the United States, and cancel scheduled visits to Cuba and Britain, to deal with the aftermath of an earthquake in Armenia.

Hailing recent improvements in relations with the United States, the Soviet president called for the creation of a new system of international relations based on the principles of global interdependence and self-determination.

After a warm farewell meeting and lunch today on Governors Island with Gorbachev, also attended by President-elect George Bush, President Reagan said, "I heartily approve" of the troop cuts. Speaking in Washington tonight, Reagan added that "if it is carried out speedily and in full, history will regard it as important -- significant."

However, Secretary of State George P. Shultz, earlier in the day, said Soviet forces will retain superiority in important categories even after the announced reductions and therefore "there will be a lot of negotiating to do" to reach an East-West military balance.

The Governors Island lunch doubled as a farewell gathering between Reagan and Gorbachev, a chance for the Soviet leader to remind Bush that he does not want the recent progress between the two countries to slow down. It was marked by warmth and good humor and took place against the backdrop of two of America's most dramatic symbols, the Statue of Liberty and the towers of Wall Street.

At the United Nations, delegates listened to the Soviet leader's speech in attentive silence, reserving their applause until the end. Before addressing the General Assembly, Gorbachev held a brief meeting with U.N. Secretary General Javier Perez de Cuellar, who escorted him to the hall.

Although Gorbachev refrained from criticizing his predecessors, many of his remarks amounted to an explicit rejection of the traditional assumptions of Soviet foreign policy.

Confirming an end to the jamming of western radio stations aimed at the Soviet Union, he said that easier international communications had made the preservation of closed societies a virtual impossibility.

By announcing a 10 percent cut in Soviet conventional forces, including 10,000 tanks, and disbanding six divisions in Eastern Europe, Gorbachev effectively challenged the traditional notion that the Soviet Union's superpower status can only be maintained through a buildup of its military strength. Instead, he called on other countries to join the Soviets in diverting military resources to economic development.

"It is now quite clear that building up military power makes no country omnipotent. What is more, one-sided reliance on military power ultimately weakens other components of national security," the Soviet leader said.

Gorbachev, confronted with trying to accomplish a difficult withdrawal of Soviet troops from Afghanistan, also appealed for a complete cease-fire in that country and cessation of all arms supplies to the warring factions by Jan. 1. He urged the United Nations to send peace-keeping forces there to help establish a broad-based government and convene an international conference to ensure a neutral and demilitarized Afghanistan.

Shultz, in a news conference following the minisummit, appeared to be unimpressed by Gorbachev's proposals on Afghanistan. He noted that the United States previously had offered the Soviets a mutual cutoff of military supplies to the Afghan rebels and the Soviet-backed Afghan government, but that Moscow had refused to stop aiding its client.

Other points made by Gorbachev during his first appearance before the world body included:

An assertion that the Soviet Union has released from prison all "persons convicted for their political or religious beliefs." This claim is rejected by western human rights activists who use a broader definition of who should be considered a political prisoner than that adopted by the Soviet authorities.

A move to resolve a dispute with the United States over a controversial radar facility at Krasnoyarsk in Siberia that the Reagan administration maintains is in violation of the 1972 Anti-Ballistic Missile treaty. Gorbachev promised to "dismantle" and "refit" parts of the radar as part of its conversion to an international space center under U.N. auspices.

A promise to submit human rights disputes to the International Court of Justice in The Hague for binding arbitration. Until recently, Soviet officials rejected western allegations of human rights violations in the Soviet Union as tantamount to interference in their country's domestic affairs.

Outlining his plan for cuts in the size of the Soviet Union's standing Army of 5 million men, Gorbachev said that the main reductions would come in Eastern Europe and the Far East. He said that the deployment of remaining Soviet troops in Eastern Europe would be substantially reorganized to provide them with a "clearly defensive" posture.

Over the past two years, Gorbachev and other Soviet leaders have developed a new military doctrine based on the notion of "sufficient defense." Until now, however, western military analysts have noticed little evidence of any substantive change in the way Soviet troops are deployed along the vital central European front.

Gorbachev said that the Soviet forces in Eastern Europe and the European part of the Soviet Union would be reduced by 10,000 tanks, 8,500 artillery systems and 800 combat aircraft by 1991. Western analysts noted that this would reduce the Warsaw Pact's present 3-to-1 advantage in tanks to about 2-to-1 over NATO while giving NATO a slight advantage in men under arms along the central front.

The principal Soviet reductions will come in East Germany, Czechoslovakia and Hungary. The two divisions of Soviet troops now stationed in Poland, guarding communication lines between the Soviet Union and East Germany, will apparently not be affected by the cuts.

Western analysts pointed out that the withdrawal of Soviet troops from Eastern Europe could have unsettling consequences at a time of major political and economic upheavals in the region. Although Soviet troops have not been used to put down internal disturbances since the 1968 invasion of Czechoslovakia, their very presence has served as a permanent reminder of the limits of Soviet tolerance.

"It could be a dangerous step for Eastern Europe. It creates the impression that Gorbachev would not intervene in the region in the event of a rebellion against Soviet control. That in itself increases the likelihood of a crisis," said Mark Kramer, a specialist in the Soviet and East European military at Harvard University's Russian Research Center.

In today's speech, Gorbachev spoke out against the "use or threat of force" as "an instrument of foreign policy" and insisted that every country had the right to choose its own form of government. If taken literally, either of these statements could seriously undermine Soviet domination of Eastern Europe.

Insisting that "freedom of choice" was "a universal principle that should allow for no exceptions," Gorbachev added: "Its nonrecognition is fraught with extremely grave consequences for world peace. Denying that right to the peoples under whatever prextext or rhetorical guise means jeopardizing even the fragile balance that has been attained."

The Soviet leader said that most of the 55,000 Soviet troops currently stationed in Mongolia along the border with China would also be brought home over the next few years. With a summit meeting scheduled between Gorbachev and Chinese leader Deng Xiaoping next spring, the Soviet Union has already been cutting back on its troop deployments in the Far East.

Gorbachev said that Soviet authorities are planning to transfer manpower and resources from the military to the civilian sectors of the economy, beginning with the conversion of two or three defense plants next year.

Turning to human rights questions, the Kremlin chief said that the Soviet Union intends to expand its participation in the work of international bodies monitoring compliance with the U.N. Declaration of Human Rights and the 1975 Helsinki accords. He confirmed an end to the jamming of foreign radio broadcasts, including the Munich-based Radio Liberty which has incurred Moscow's wrath in the past because of its detailed reporting on Soviet internal developments.

On the controversial issue of Jewish emigration from the Soviet Union, Gorbachev announced a concession that could relieve the plight of many Soviet Jews who have been barred from leaving the country because of their alleged past access to military secrets. He said that strict time limitations would now be observed to the secrecy rule, which has frequently been applied indiscriminately in the past.

"This removes from the agenda the problem of the so-called refuseniks," Gorbachev said.

On multilateral international issues, Gorbachev called for an expanded role for the United Nations and praised "the recent reinvigoration of its peace-keeping role." He said that new possibilities were opening up for the world body in advancing economic, scientific, technological and environmental concerns.

Gorbachev said the Soviet Union is ready to declare a lengthy moratorium -- for up to 100 years -- on the debts owed it by the least-developed countries.

ARMS CUTS: Soviet armed forces will be reduced by 500,000 men and 10,000 tanks within two years. Six tank divisions will be withdrawn from East Germany, Czechoslovakia and Hungary and disbanded by 1991, reducing Soviet forces in those countries by 50,000 men and 5,000 tanks.

AFGHANISTAN: A cease-fire in place was proposed for Jan. 1, linked to an end to supplying of arms to either side. U.N. peace-keeping forces were requested to help set up a broad-based government in Kabul, and an international conference was asked on a neutral, demilitarized Afghanistan.

WORLD DEBT: Moscow is willing to suspend payments for to up 100 years on debt owed to it by the least developed countries, and to write off some debts. The United Nations was urged to consider other steps.

HUMAN RIGHTS: Changes in Soviet law were promised to ensure that no citizen will be persecuted for political or religious beliefs.

U.S. RELATIONS: The incoming Bush administration was promised a negotiating partner ready to continue work on cuts in strategic arms and conventional forces in Europe.