Soviets Will Focus on Next Summit in Meeting With Baker : Diplomacy: Moscow is upbeat about potential progress in the talks in a Siberian city today.

Secretary of State James A. Baker III and Soviet Foreign Minister Eduard A. Shevardnadze flew to this Siberian city Tuesday for wide-ranging talks that the Soviets said will focus on quick preparations for another superpower summit this year.

On an agenda running the gamut of U.S.-Soviet relations from nuclear weapons reductions talks to regional disputes such as Afghanistan and Cambodia, Soviet officials expressed repeated confidence that progress will be made. The two days of negotiations in Irkutsk that open today promise “interesting results,” Foreign Ministry spokesman Yuri A. Gremitskikh said.

Shevardnadze, speaking to Soviet reporters aboard his Ilyushin 62 jetliner as he covered the 3,100-mile distance from Moscow, disclosed that President Bush and Soviet President Mikhail S. Gorbachev had agreed during their meeting off the island nation of Malta last December to hold still another superpower summit before the end of 1990.

The leaders already have met a second time, in Washington last June. The Soviet news agency Tass, summarizing Shevardnadze’s in-flight remarks, said that “there was extremely little time left to prepare the new summit” and indicated that the Soviet leadership wants that issue to be a major discussion topic in Irkutsk.

The Tass report of Shevardnadze’s comments gave no details about the timing or venue of the third meeting between the presidents. Alixe Glen, White House deputy press secretary, said in Washington that a superpower summit probably will be held in Moscow in 1991, but could come earlier if a nuclear weapons reduction treaty is ready for signing.

A conclave of the leaders of the 35 nations involved in the Conference on Security and Cooperation in Europe is due to be held in Paris in November, and it is conceivable that Bush and Gorbachev could decide to meet then.

Shevardnadze said his discussions with Baker in this city of 630,000 near the Soviet Union’s biggest freshwater lake, Lake Baikal, will concentrate on preparations for the summit as well as on European security, bilateral issues and regional problems.

Aides traveling with Baker, who arrived early today, continued to play down speculation that a final agreement between the superpowers to bring about an end to the 11-year-old war in Afghanistan would be reached in Irkutsk, but Soviet officials seemed decidely upbeat.

“The issue of a settlement is now being posed differently,” Shevardnadze told journalists. He said the superpowers’ positions are “definitely coming closer together,” Tass reported.

Speculation increased that an Afghan deal was in the offing when the country’s Moscow-backed president, Najibullah, flew to the Soviet Union earlier this week. Gremitskikh, the Foreign Ministry spokesman, told a government news briefing in Moscow that Najibullah was in the country “specifically to undergo medical examinations.”

The United States supports the Pakistan-based Muslim guerrillas fighting Najibullah’s government, which lost its Soviet allies on the battlefield when the Kremlin pulled out its more than 115,000 soldiers in February, 1989.

Under the emerging framework of a U.S.-Soviet agreement, according to Bush Administration officials, Najibullah would cede effective power to an interim government that would oversee national elections.

U.S. negotiators previously had insisted that the former chief of Afghanistan’s dreaded Khad secret police step down. Now they say Najibullah could remain as president during elections, provided he cedes control of the army, state-owned media and secret police to a neutral body.

Baker flew to Irkutsk after a five-day trip to Southeast Asia during which he failed to secure the backing of the region’s foreign ministers for the abrupt U.S. decision to end eight years of support for the Cambodian resistance and begin talks with Vietnam, a Soviet ally that backs the Cambodian government.

The Administration’s goal was to distance the United States from the Khmer Rouge, the most powerful member of the three-party Cambodian resistance coalition. The Khmer Rouge killed an estimated 1 million Cambodians when it held power in 1975-78.

Shevardnadze said it was essential to “strengthen the sides’ mutual understanding” on Cambodia, now that American policy has changed, and to map out a program for further action to end that country’s 12-year-old conflict.

One of Shevardnadze’s top deputies, Alexei A. Obukhov, also sounded optimistic about the chances for progress in resolving regional disputes.

“Some achievements have been made in the area, and they should be consolidated by appropriate decisions,” the Soviet deputy foreign minister had emphasized as he left Moscow for Irkutsk, Tass reported.

The Irkutsk meeting will be the ministers’ 16th. Shevardnadze told reporters that like Jackson Hole, Wyo., where he and Baker held talks last September, this eastern Siberian city was chosen in large part for the virtue of remoteness.

“Less time is wasted on protocol, and there are time and the conditions for a truly working atmosphere,” Shevardnadze noted.

After their talks, Baker and Shevardnadze will take a cruise on Lake Baikal. The secretary of state is to fly to Mongolia on Thursday for talks with the government as well as a hunting trip.

Dahlburg reported from Moscow and Mann reported from Irkutsk.