NEWS ANALYSIS : MEETING IN MOSCOW : Summit Fails to Peak Past a Diplomatic Vale : Politics: Analysts see meeting’s token agreements as indicative of a stalemate in relations.

President Clinton’s sixth and least successful meeting with Russian President Boris N. Yeltsin marks another lurch in superpower relations, which have swung from Cold War animosity to post-Communist amity and back to acrimony again.

Clinton and Yeltsin hailed the token agreements of their three-hour discussion as evidence of a mature, strengthening relationship, while analysts deemed the positive spin they put on their virtual stalemate as a doomed effort at damage control.

One senior Clinton Administration official acknowledged dejectedly that U.S.-Russian ties have suffered severe damage in recent months, with disputes over NATO expansion, the war in Chechnya and a pending Russian sale of nuclear technology to Iran dispelling illusions that confrontation was buried with hard-line communism.

“We have to break out of this cycle of manic depression,” the official said of the mood swings lately defining relations between Washington and Moscow.

Admitting that little was achieved Wednesday on any of the contentious topics dividing the countries, he warned that the United States and Russia have exhausted the era of good feeling that prevailed in the first Clinton-Yeltsin meeting in Vancouver, Canada, two years ago.

The easing of the nuclear threat between their nations and the end of bitter ideological confrontation between them have allowed the two presidents to meet in a less menacing atmosphere.

But their four summits and two head-to-head caucuses, during gatherings of the Group of Seven leading industrial nations, have failed to close much of their political distances.

“Progress will be grinding, slow and there will be setbacks,” the Administration official said, describing Russia’s opposition to expansion of the North Atlantic Treaty Organization as an example of the standoffs forcing both countries to take a more sober view of the future.

“Yeltsin is not going to come out tomorrow for NATO expansion” to include former Warsaw Pact states, he said. “There’s nothing in it for Russia, and no one here supports it.”

Likewise, the Russian president’s rebuttal of criticism over the war in Chechnya reflected the hard edge that has lately been exhibited by the Kremlin.

Yeltsin described the suppression of secessionists there as “an internal matter for Russia” and denied that fighting was continuing even as the leaders spoke.

His steadfast refusal to cancel the $1-billion nuclear deal with Iran also testified to a tougher tone being taken by the summit host, who scored political points simply by securing Clinton’s visit.

“Yeltsin gained the upper hand the minute Clinton agreed to come here, because this is interpreted by Russians as a sign of American support,” said Andrei V. Kortunov, deputy director of the USA-Canada Institute here.

There is no cause for disappointment in the decline of trust and slackening pace of cooperation between the United States and Russia, he said, because neither leader approached this week’s summit with any positive expectations.

“There can be no compromise on any of the disputes because neither leader is in any position in his own country to accomplish this,” Kortunov said of Yeltsin’s single-digit support level in recent polls and the growing chorus of Republican voices calling for a cutback in U.S. aid to Russia.

Prospects for resolving the main issues frustrating the two nations’ relations were so slim on the summit’s eve that some analysts suspect that Clinton and Yeltsin exaggerated their few agreements in a mutual effort to save face.

While Yeltsin did not budge in his intention to deliver on the lucrative nuclear deal with Iran, he told Clinton that he will cancel the pending sale of a gas centrifuge that can be used to enhance nuclear fuel for weapons production.

A Western diplomat likened the “compromise” on the Iran deals to letting a dangerous man buy a gun while forbidding him a jackknife.

Yeltsin also made a symbolic concession in agreeing to join NATO’s Partnership for Peace.

Yet he and other Kremlin officials have continued to disparage NATO expansion plans as destabilizing and likely to create new divisions in Europe.

Administration officials tried to be upbeat, describing the new phase of relations as more realistic than the heady optimism that emerged after Russians threw off one-party rule and made Yeltsin Russia’s first freely elected president.

State Department spokesman Nicholas Burns cast the thorny disputes over NATO, Iran and Chechnya as predictable rough spots that occur in any bilateral relationship.

“It is absolutely normal to have relations filled with major areas of convergence and minority areas of divergence,” Burns said.

Another official said that, while progress was not dramatic at the summit, at least the Russians “are no longer pouting in their tents.”