"As the United States and our allies have made clear, military intervention and violation of international law will bring increasing costs for Russia - not only due to measures imposed by the United States and our allies but also as a direct result of Russia's own destabilizing actions," White House spokesman Jay Carney said in a statement.
"In this century, we are long past the days when the international community will stand quietly by while one country forcibly seizes the territory of another," he said.
