U.S. warns Russia it faces isolation, sanctions in coming days

WASHINGTON (Reuters) - The White House warned President Vladimir Putin on Sunday that Moscow would face sanctions in coming days and international isolation that will hurt Russia's economy, as Washington fumed over a referendum in Ukraine's Crimea region that it was powerless to stop.

"We are putting as much pressure on the Russians as we can to do the right thing," White House senior adviser Dan Pfeiffer said as voters in Crimea, under the control of Russian forces, decided whether to break away from Ukraine and join Russia.