Corker: 'We're going to lose eastern Ukraine'

The top Republican on the Senate Foreign Relations Committee sees Russia taking full control of eastern Ukraine unless there's a major change in the approach that the United States and its allies are taking in assisting Kiev.

"I think we're going to lose eastern Ukraine if we continue as we are, and I think it's going to be a geopolitical disaster if that occurs," Sen. Bob Corker said Sunday on NBC's "Meet the Press."

"I think Russia is going to do it over time the way they're doing it with black ops, intimidation," he said.

(Also on POLITICO: Ukraine PM: ‘God knows’ where Putin will stop)

The Tennessee Republican said the Obama administration hasn't done much to help the Ukrainians with what he views as a largely passive approach to the actions of President Vladimir Putin's Kremlin. "I think the administration is basically saying to Russia, look, don't do anything overt, don't come across the border with the 40,000 troops, don't embarrass us in that way, but you can continue to undermine the sovereignty of Ukraine by doing the things that you've done."

Corker said he's pushed the administration to be more forceful and hopes to see the United States impose tougher sanctions on Russia and offer more substantive military aid to Ukraine.

"I really do believe we should be sanctioning some of the companies in the energy sector. I think we should hit some of the large banks there," he said. "And certainly we should beef up our security relationship with Ukraine."