The upper house of the Russian parliament, the Federation Council, has ratified a treaty of friendship with Ukraine, on the condition that Ukraine ratifies three treaties on the status of the Black Sea Fleet.
Other contentious issues, such as the future of the Crimean Pensinsula, have been settled in the document.
The treaty's acceptance by parliament was delayed, partly because of objections by Russian nationalists.
They criticized the document for recognising Ukrainian control of Crimea, which was transferred to Ukraine from Russia in 1954, and Sevastopol, the base of the Black Sea Fleet, which has been divided between Russia and Ukraine.
Correspondents say it's likely Ukraine will ratify the Black Sea Fleet agreements.
Kiev has already ratified the friendship treaty. A BBC correspondent in Moscow says Russia's ratification of the friendship treaty represents a personal triumph for Prime Minister Yevgeni Primakov.
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