MOSCOW -- Boris N. Yeltsin and the leaders of eight other Soviet republics lined up with Mikhail S. Gorbachev on the steps of a grand pre-Revolutionary country estate yesterday and assured the world that the Soviet Union is not flying to pieces.
The republic leaders -- who are becoming key players in the politics of the country and who range in personality from grateful obedience to determined unruliness -- declared that they had fallen into step behind the Soviet president as he prepares to head off to next week's economic summit in London.
Calling it "a decisive turning point in our national history," Mr. Gorbachev achieved an agreement that was short on details but long on symbolism.
It will enable him to go to London with the backing of nine of the 15 Soviet republics -- the other six want to secede no matter what --and present an appeal as the leader of a nation with a single program.
Mr. Gorbachev did not say what he plans to ask of the seven Western economic powers, but he made it clear that the Soviet Union is hoping to combine economic and political reforms with foreign investment.
The newly elected Russian president, Mr. Yeltsin, who in the past has seemingly enjoyed taking pot shots at Mr. Gorbachev, stood soberly next to him yesterday and said, "The most important position that was worked out today is that the president of a huge power, as the representative of the republics as well, is going in order to express their position."
Going along with Mr. Gorbachev as he attempts to gain the aid of the Western nations is important, Mr. Yeltsin suggested, "because the transition to a market economy will be for our people and all of us very difficult."
Western officials have made it clear that they are unlikely to hand over large sums of money to Mr. Gorbachev next week, but yesterday's show of harmony clearly was aimed at showing that the Soviet Union is a coherent nation that can be dealt with, and one that is committed to change.
"For real, serious, deep reform, of course international cooperation is necessary," said Vitold Fokin, the Ukrainian prime minister. "Of course support is necessary. Of course investment is necessary. But that doesn't mean we've decided to live in debt. We put our hope in our own powers."
Mr. Gorbachev took the opportunity yesterday to emphasize that those powers will be greater if the nation holds together -- through a new treaty among the republics -- than if it flies apart. Although the break-up of Yugoslavia wasn't mentioned on the steps outside the neo-classic estate yesterday, events there have been a powerful and frequently cited reminder here of what could happen.