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(CNN) – Russia ordered surprise military exercises on Ukraine's doorstep Wednesday as tensions in that country's southern Crimea region simmered.
A big fear of the U.S., the European Union, and NATO is that Russia may send troops in.
"We urge outside actors in the region to respect Ukraine's sovereignty and territorial integrity and end provocative rhetoric," the White House said in a statement today.
"They're trying to be fair. They're saying we're talking to Russia, we're talking to anybody else, but They're really talking to Russia. It's diplomatic happy talk," former Pentagon official Peter Brookes told CNN's "The Lead with Jake Tapper."
But these Russian drills could turn into the real thing, provocation from Ukraine or that region could send Russian troops across boarder, says Brookes.
"I'm a little worried," said Brookes. "I don't want to go out on a limb and I don't think Russian tanks will necessarily roll into Ukraine, but there are ethnic Russians in the eastern part of the country."
The situation reminds Brookes of the conflict in Georgia in 2008, when Russia granted passports to Georgians of Russian descent, claimed them as citizens in need of protection, then held exercises before they went in.
"Russia has a lot of interest there. And if there's violence perhaps against ethnic Russians in Ukraine, I wouldn't rule it out," said Brookes.
For more of our interview with former Pentagon official Peter Brookes, check out the video above.