Ukrainian crisis

US President Barack Obama has urged his Russian counterpart Vladimir Putin in a phone call to agree to a peace deal with the Ukrainian government.

"If Russia continues its aggressive actions in Ukraine, including by sending troops, weapons, and financing to support the separatists, the costs for Russia will rise," said a statement issued by the White House on Tuesday.

The Kremlin, however, emphasised in its statement about the call that the Ukraine crisis was an "internal" conflict.

Kiev and the West accuse Moscow of supplying and training the heavily armed separatists, but Russia denies the claims. 

Obama warns Putin of 'rising costs' over Ukraine