SEOUL -- Soviet President Mikhail Gorbachev's expected meeting today with South Korean President Roh Tae Woo marks the clearest sign yet that the Cold War's grip on Asia is easing, according to diplomats, South Korean officials and political analysts.

South Korea views the San Francisco session -- the first formal talks between the two nations' leaders -- as a profound triumph that is likely to clear the way this year for full diplomatic relations with the Kremlin, Seoul's enemy for four decades.

South Korea has courted the Soviet Union since 1988, partly as a means of seeking improved ties with Communist North Korea. Trade between Seoul and the Soviets reached $600 million last year, and today's summit is expected to give a green light to large new loans and investments by South Korea in the Soviet Union. Officials here, however, have denied local newspaper reports that Seoul is considering as much as $3 billion in loans to Moscow.

Shortly before his departure for San Francisco, Roh expressed hope that his talks with Gorbachev would provide a way "to spread to northeast Asia, especially to the Korean peninsula, the waves of openness and cooperation now sweeping the world."

At departure ceremonies, Roh said he planned to discuss bilateral relations with the Soviet leader along with ways to achieve "peace and unification" of the two Koreas. "Korea now remains the only country on earth that is still divided as a legacy of the Cold War," Roh said. "We must not allow our national division to continue into the 21st century."

North Korea, the Soviets' traditional ally, has sharply criticized the San Francisco summit. Estrangement between Pyongyang and Moscow has increased since the Soviets opted to attend the 1988 Summer Olympics in Seoul rather than honor a North Korean boycott. Despite the harsh rhetoric, diplomats and officials say, North Korea will likely continue a recent pattern of hesitant and modest moves away from isolationism.

The Soviets, who still have a strong economic and political presence in Pyongyang, are expected to act as mediators between the Koreas. The United States does not have diplomatic relations with the North.

"My hat's off to them for a very high-level diplomatic accomplishment," Donald Gregg, the U.S. ambassador to South Korea, said here after the San Francisco session was announced. Roh last week underscored his diplomatic goal, saying, "Since there is no way open for me to go to Pyongyang, I have to go there by way of Moscow."

Officials here play down suggestions that today's meeting will yield specific or spectacular agreements. "To do business, they have to get to know each other first," said a Foreign Ministry official. "This is just to set the framework."

Kim Young Sam, chairman of South Korea's ruling party, said, nevertheless, last week after a meeting with Roh that the Soviet and South Korean presidents are expected to agree to upgrade their consular ties to full relations by August and to exchange visits to each other's countries by next year.

The Koreas are technically still at war nearly four decades after their bloody conflict ended in a truce. Their common border remains sealed by more than 1 million soldiers, and people on each side are barred from any contact or movement across the dividing line, the 38th parallel. Defense Secretary Richard B. Cheney has called the Korean peninsula the most volatile area where U.S. forces are stationed.

Political changes in Europe have far outpaced developments in Asia, where some of the enmities and alliances of the Cold War are just beginning to shift. Tokyo's relations with Moscow remain chilly because of Soviet control over the Kuril Islands, occupied by the Soviets after World War II. And despite new commerce across the Yellow Sea, South Korea and China still do not have direct air links.

The announcement of the Roh-Gorbachev meeting stunned Asian officials. The Soviet decision to give de facto recognition to a country with which it once waged war has raised cautious hopes for other diplomatic shifts throughout Asia, although not necessarily in the immediate future.

Gorbachev wants to improve his country's limited economic ties with Japan, and some political analysts suggest that the Soviet leader is trying to nudge Japan by offering a trade opening to its economic rival, South Korea. Others believe Gorbachev may be ready to make compromises on the Kuril issue.

"Japan is the key element," said Han Sung Joo, chairman of Korea University's political science faculty.

Beijing, like Moscow, is tempted by Seoul's ability to offer cheap consumer goods and industrial know-how. Despite its ties to Pyongyang, Beijing is expected to increase its quiet trade and other contacts with Seoul, while staying one step behind the quickly advancing Soviets. Diplomats in Beijing have been quoted as saying a high-level Soviet delegation will visit the Chinese capital next Sunday for sensitive talks about Korea.

In South Korea, the plan to hold the Roh-Gorbachev meeting in the United States -- with crucial American diplomatic support -- is seen as likely to help counter growth of anti-Americanism stemming in part from resentment over what is viewed as U.S. efforts to keep Seoul in a diplomatic straitjacket, estranged not only from North Korea but also from the Soviets and Chinese.

"It will help erase a false and persistent notion among Koreans that this {new South Korean assertiveness} is something the U.S. doesn't like," a diplomat said.

North Korea has warned of "a serious political consequence" from the Roh-Gorbachev meeting. When the once-Communist nations of Eastern Europe recently began recognizing South Korea, the North also initially lashed out, but it now appears to have reluctantly accepted the changes. Many experts say North Korea will follow the same pattern now.

Few diplomats here expect today's meeting to spark immediate changes in the North's stance toward the South, although they say shifts are likely sooner or later -- particularly once President Kim Il Sung passes from the scene and power is transferred to his son and political heir, Kim Chong Il.

"North Korea will try to find a way of establishing a relationship with the United States without opening up to South Korea," said Han of Korea University.