KIEV - U.S. Vice President Joe Biden on Friday condemned Russian behavior in Ukraine as “unacceptable” and urged it to abide by a September peace deal by adhering to a ceasefire and removing military forces from the country.

Addressing himself rhetorically to Kremlin leader Vladimir Putin after holding talks with Ukrainian President Petro Poroshenko, Biden said: “Do what you agreed to do, Mr. Putin.”

Referring to Russia’s annexation of the Crimea in March and its backing for separatist rebels in eastern Ukraine, Biden, in a statement to the press alongside Poroshenko, said Russian behavior was a “flagrant violation of the bedrock principles of the international system.”Biden said the United States would always support a democratic, reformist Ukraine, but he made no specific mention of any fresh aid.

Russia denies arming the separatists or sending its troops across the border.(Reuters)