The highlight of the fifth Sino-Russian summit was a declaration laying to rest wrangles over implementation of a 1991 accord that mapped out the entire 2,800-mile frontier.
Border tension between China and Russia has flared on and off for several hundred years since the days of the tsars. It erupted most recently at the height of ideological confrontation between Moscow and Peking as they vied for supremacy in the Communist world.
Red Army soldiers of the former Soviet Union fought skirmishes with Chinese People's Liberation Army troops in 1969 on ice floes along frozen border rivers.
President Jiang said the agreement would "create good guarantees for peace, stability and calm on the Russian-Chinese border". Experts have been haggling over where to place markers on the eastern frontier stretching in an arc from Mongolia to the Sea of Japan.
There is no dispute over a 32-mile wisp of border in mountains to the west between Kazakhstan and the westernmost tip of Mongolia.
At a ceremony in the Great Hall of the People, the Chinese vice-Premier, Li Lanqing, and the Russian First Deputy Prime Minister, Boris Nemtsov, signed three documents aimed at boosting a worryingly low level of trade.
Under a framework agreement on the pipeline, gas would flow from Siberia to China's Pacific Coast for 30 years. The supplies would also serve Japan and South Korea.
Mr Yeltsin hailed the success of his third state visit to China, and stressed a personal chemistry with Mr Jiang of a kind that was pointedly absent when the Chinese leader met the American President Bill Clinton in Washington last month.
Mr Yeltsin and Mr Jiang locked in a bear hug at the steps of Peking's Great Hall of the People, and after they emerged from their summit they spoke warmly of their grandchildren at a light-hearted meeting with reporters. A Chinese foreign ministry spokesman quoted Mr Jiang as saying: "Yeltsin is an old friend, every time we meet it is happy and intimate."
Bitter rivalry between Moscow and Peking from 1960, following their close alliance of the previous decade, is now almost completely forgotten.
The relationship has blossomed since the late 1980s and is now described by both countries as a "constructive partnership".
-- Reuters, Peking