At least 15 other countries are prepared to back the freeze, says Russia's energy minister.
Oil prices have slid more than 25 percent so far this year
The measure is part of a deal wrapped to keep the U.S. government open through September.
A U.S. and EU oil embargo would cripple Russia overnight as it relies largely on pipelines to the West.
The U.S. is starting to export oil from its fracking boom, but selling to Asia might prove difficult