Poland said that a renewed buildup of Russian troops on Ukraine’s border raises the specter of a possible invasion, as President Vladimir Putin ordered his government to prepare a response to U.S. and European sanctions.

“Unfortunately, Russia has restored its combat-readiness on the Ukraine border with more than a dozen battalion-sized combat groups,” Polish Foreign Minister Radoslaw Sikorski, told TVN24 BiS television yesterday, while giving no indication that an invasion was imminent. “There’s a lot of equipment. This is the sort of thing one does to exert pressure or to invade.”

Ukraine expressed alarm about a new deployment of Russian forces on its frontier as it pressed an offensive against pro-Russian separatists. There’s “active combat taking place” on the outskirts of Donetsk, with two civilians killed, the city council said on its website last night.

Sikorski, whose country is among the EU nations seeking the toughest response to the Kremlin’s policy over Ukraine, said any incursion would be under the guise of a peacekeeping mission.

David Fuller's view

Putin is predictable.  He will have to demonstrate that he is the strong man, to keep critics in Russia largely silent.  He will also hope to intimidate European leaders.