Soviet Heirs, U.S. OK Nuclear Cuts : Arms control: The agreement clears the way for ratification of the START treaty. Russia will become the sole successor to Kremlin’s arsenal of atomic weapons.

Clearing the way for ratification of the most comprehensive arms control agreement of the Cold War era, Secretary of State James A. Baker III and senior officials of the four nuclear-armed states of the former Soviet Union signed an agreement Saturday that makes Russia the lone successor to Moscow’s atomic arsenal.

The signing ceremony, carried out in an eerie near-silence in an ornate hotel ballroom, requires Ukraine, Kazakhstan and Belarus to eliminate the strategic nuclear weapons on their territories during a seven-year period set by the Strategic Arms Reduction Talks treaty to accomplish a one-third cut in superpower nuclear stocks.

The START pact was signed last July by President Bush and then-Soviet President Mikhail S. Gorbachev but was stalled since then by the messy breakup of the Soviet Union. More than nine years in the making, the treaty once appeared to be unrealistic, even visionary. But now Washington and Moscow are ready to start talking about far greater reductions.

Ever since the Soviet Union disintegrated in December, the U.S. government has been trying to cobble together the protocol signed Saturday by Baker, Russian Foreign Minister Andrei V. Kozyrev, Ukrainian Foreign Minister Anatoly Zlenko, Kazakh State Counselor Tulegen Zhukeyev and Belarus Foreign Minister Petr Kravchenko.

Although the disputes seem arcane, the final agreement was so delicately balanced that Baker imposed a rare gag order on the signing ceremony. A senior State Department official hinted that the U.S. side was concerned that if anyone said anything controversial at the ceremony it might reopen the contentious negotiations.

Another senior official said the problem was primarily one of assuring Ukraine, Kazakhstan and Belarus that they were being taken as seriously as giant Russia.

“We had to deal with the sensitivities and political status of emerging states,” the official said.

The pact was signed in five languages, including the seldom-used Belarussian tongue, in another bow to new nationalistic sensibilities.

In return, Ukraine and Kazakhstan, now the world’s third- and fourth-most-powerful nuclear powers, agreed to eliminate all of the weapons on their territory and join the Nuclear Non-Proliferation Treaty as non-nuclear states. Belarus, which has only a handful of nuclear weapons, agreed to do the same.

In a written statement issued after the ceremony, Kozyrev suggested that Russia would delay the START ratification until the other three republics join the non-proliferation treaty. Baker clearly was not pleased by the development, but the U.S. side decided not to let it upset the protocol.

A senior official said that Washington will urge Ukraine, Kazakhstan and Belarus to accept limits set by the non-proliferation treaty as soon as possible, thus eliminating Russian concerns.

“The situation may not arise, and we will face it at the time if it does,” the official said. Nevertheless, Kozyrev’s written comments were the sort of thing Baker wanted to keep from being said at the ceremony.

In his own written statement, Baker said that START, and the new protocol, “significantly lowers the risk of nuclear war by radically reducing strategic offensive arms and enhancing strategic stability.”

As each of the five ministers signed his name on each of the five documents, each appeared to be unaccustomed to sitting in silence in front of waiting reporters. Kozyrev stared at the press corps and placed a hand over his eyes. Baker held up crossed fingers on each hand.

Baker and Kozyrev plan to meet today to start negotiating even deeper cuts in nuclear arsenals than required by the START treaty. Both Bush and Russian President Boris N. Yeltsin have already suggested major reductions, but they are far apart on details. Yeltsin is scheduled to visit Washington on June 16 and 17 for a summit that may be dominated by talk of arms reduction.

Zhukeyev, in Washington last week with Kazakh President Nursultan Nazarbayev, accompanied Baker on a U.S. Air Force jetliner from Washington to Lisbon. Talking to reporters aboard the plane, Zhukeyev said his government must now convince its people that Kazakhstan will be safe without the nuclear arms stationed there.

He said Kazakhstan determined that it did not need the weapons after six of the 11 members of the Commonwealth of Independent States agreed to a mutual defense pact earlier this month. Moreover, he said, Baker reiterated a 24-year-old U.S. pledge to support any non-nuclear power coming under nuclear attack. The commitment, issued at the time the non-proliferation treaty was signed, does not specifically require U.S. military action.

The five foreign ministers were in Lisbon to attend a conference to coordinate aid to the former Soviet Union. The meeting attracted more than 60 top officials from such First World aid givers as the United States and Japan to such financially strapped governments as Egypt and Romania.

Although proceedings of the conference, which continues today, were secret, Baker’s opening speech was made public. The secretary of state proposed three new U.S. initiatives, including a $25-million program to improve the safety at the 37 nuclear power reactors scattered across the territory of the former Soviet Union in an effort to prevent accidents like the 1986 reactor fire at Chernobyl in Ukraine.

“The dangers of Chernobyl are real, and this initiative aims to reduce the risk of accidents at Soviet-designed nuclear reactors by addressing safety deficiencies of those reactors as soon as possible,” Baker said.

Baker also said the United States is ready to copy a European Community plan for selling donated food on the free market, using the receipts from such sales for social programs. The objective is to stimulate market economics while raising money for much-needed welfare. He also promised additional U.S. funds to help the former Soviet republics convert their industry from military to peacetime pursuits.

The conference was called to review the progress of humanitarian programs launched after a similar meeting in Washington in January.

Baker also called on all nations attending the conference to “use whatever influence you have” to deter Serbian aggression against its neighbors in the now collapsed Yugoslavia.

“Every attempt at peace has been blocked, and now we are witnessing human suffering on a terrible and massive scale,” Baker said. “No longer should the international community tolerate this barbarity, this affront to our collective conscience.”

He did not suggest specific measures beyond the ones he announced Friday--closing Serb-controlled Yugoslav consulates in San Francisco and New York, breaking all contacts with the Yugoslav army, permanently withdrawing the U.S. ambassador from Belgrade and refusing to recognize Serbia and its ally, Montenegro, as the legal successor to the Yugoslav state.

But Klaus Kinkel, Germany’s new foreign minister, told reporters after a meeting with Baker that the European Community is considering a trade embargo and other economic steps to “close down” the Serbian economy. He added that he would support an oil embargo.

Luxembourg Foreign Minister Jacques Poos reportedly said the United States and the European Community are considering a request to the U.N. Security Council for a military force to protect the airport at Sarajevo, the capital of Bosnia-Herzegovina.