(FORTUNE Magazine) – Even as the Bush Administration announced a $1.5 billion free-food-aid program for the Soviet Union, President Mikhail Gorbachev was publicly snubbed by the Russian republic. It's withholding tithes to the central government and setting off on its own self-charted path to economic reform. Meanwhile, Russian President Boris Yeltsin is facing rebellion from his own domain: All 20 of Russia's semiautonomous regions have declared sovereignty, and some commentators have predicted war in the Caucasus Mountains over competing claims by rebel regions for the area's fertile land. Yeltsin is trying to push a stronger economy as a way to hold the republic together. Investments and loans from abroad are key to his plans. So, at the urging of his new Deputy Prime Minister, Yegor Gaidar, 35, he has promised that Russia will guarantee the $84 billion owed foreign bankers by the 15 republics that constituted the U.S.S.R. With more than 90% of the country's known oil reserves under the Russian republic's soil, Yeltsin is threatening to force delinquent republics to pay Russia hard currency for their oil if they refuse to honor commitments to Western bankers. That should make them think twice before they default on their payments -- and help build Yeltsin the international credit rating that he needs.