Vladimir Putin on Thursday denied the White House claim that Russia is assisting separatists in eastern Ukraine - but did not rule out sending troops into the region.
During a televised phone-in, Russia's president reminded the audience that his country's parliament had granted the right to use military force in its former Soviet neighbor.
"I really hope that I do not have to exercise this right and that we are able to solve all today's pressing issues via political and diplomatic means," he said, according to a translation by Reuters.
Ukraine sent troops to the region but their effort appeared to fall flat Wednesday, with some personnel carriers ending up commandeered or defected and other troops returning by bus.
Putin called Kiev's attempt to stop the separatist movement in the region a "grave crime."
"Instead of realizing that there is something wrong with the Ukrainian government and attempting dialogue, they made more threats of force ... this is another very grave crime by Kiev's current leaders," Putin said.
Reuters contributed to this report.