[McGruff]

From their perspective:

The Kremlin said on Friday the arrival of about 300 U.S. paratroopers in Ukraine to train Kiev’s National Guard could destabilize the situation in the east of the country, where pro-Russian separatists are fighting Ukrainian government forces.

“The participation of instructors or specialists from third countries on Ukrainian territory, where the domestic Ukrainian conflict is unresolved ... could destabilize the situation,” Kremlin spokesman Dmitry Peskov told reporters in Moscow during a conference call.

http://www.reuters.com/article/2015/04/17/us-ukraine-crisis-russia-usa-idUSKBN0N80PR20150417

[Toddsterpatriot]

The Kremlin said on Friday the arrival of about 300 U.S. paratroopers in Ukraine to train Kiev’s National Guard could destabilize the situation in the east of the country,

And then Putin would have to send in (more) Russian troops to bring back stability?

The participation of instructors or specialists from third countries on Ukrainian territory,

Only invading Russian specialists allowed?