WASHINGTON -- Vice President Joe Biden said in an interview that Russia's economy is "withering," and suggested the trend will force the country to make accommodations to the West on a wide range of national-security issues, including loosening its grip on former Soviet republics and shrinking its vast nuclear arsenal.

Mr. Biden said he believes Russia's economic problems are part of a series of developments that have contributed to a significant rethinking by Moscow of its international self-interest. The geographical proximity...