Secretary of State James A. Baker III on Monday called on the Soviet Union to abandon the so-called Brezhnev Doctrine used to justify military intervention to block reforms in communist countries.

Baker, in his first speech to an international forum, also announced that President Bush is exploring ways to accelerate the removal of U.S. chemical weapons from West Germany.He said the Soviet Union has enormous stocks of such arms threatening Europe and called on Moscow to join the United States in mutual destruction of "these frightening weapons."

Baker spoke at a meeting of 35 foreign ministers gathered in Vienna's Hofburg palace to launch talks on reducing conventional weapons across Europe.

In a largely conciliatory speech, he urged the Soviet Union to put into practical use the "new thinking" guiding Soviet President Mikhail S. Gorbachev's foreign and domestic policies.

"New thinking and the Brezhnev Doctrine are in fundamental conflict," he said.

"We call today upon General Secretary Gorbachev to renounce the Brezhnev Doctrine - beyond any shadow of a doubt," he said.

Baker told his fellow ministers that all Europeans should have the freedom "to have a say in decisions which affect their lives" and to express their political differences, as well as the freedom "to be safe from military intimidation or attack."

"Those in the East," he said, "should be free of the fear that armed Soviet intervention, justified by the Brezhnev Doctrine, would be used again to deny them choice."

The doctrine, named for the late Soviet President Leonid I. Brezhnev, was invoked by Moscow to justify the 1968 Soviet-led invasion of Czechoslovakia to crush the liberal communist reforms of then party leader Alexander Dubcek.

Baker's speech made favorable references to the change Gorbachev has instituted. "The rhetoric of Soviet foreign policy is being reshaped with less emphasis on the use of force," he said.

At another point, he said that as Europe approaches the end of the decade, "new horizons are beckoning" and that "realism has begun to triumph in the Soviet Union."

Baker began his three-day visit to the Austrian capital on Sunday with meetings with the foreign ministers of Hungary and Poland, sending a signal that the Bush administration wants to encourage those countries' increasing political and economic reform.

Baker said in his speech that "people want freedom, freedom of the mind, freedom in the home" behind what has become "a rusting Iron Curtain."

He said while the East should be free of the prospect of Soviet intervention, those in the West should be free of the fear of Warsaw Pact forces pointed in their direction.

"We shall never be able to set East-West relations on an irreversible course toward enduring improvement unless we deal with the huge conventional military imbalance in Europe," he said.

Baker called Gorbachev's offer in December to withdraw six tank divisions and 50,000 men from eastern Europe "a very good start."

But even after such a pullout, he said, the Warsaw Pact would retain a 2-to-1 edge in tanks and artillery.

Baker said the North Atlantic Treaty Organization would propose once the negotiations begin Thursday an overall limit of 40,000 tanks among the 16 NATO and seven Warsaw Pact countries and "confidence-building measures" later to reduce the possibility of surprise attack.

However, he said, "change in the military balance is only one part of the process." Only when the causes of the historic division of Europe have been removed . . . will it be possible to eliminate the military confrontation."