Russian President Vladimir Putin has denied a rift with German Chancellor Angela Merkel, who has adopted a tough stance on Russia's actions in Ukraine.

As the cease-fire in Ukraine effectively collapsed and convoys of unidentified weaponry were recently seen in rebel-held areas, some European leaders called for more sanctions against Russia and the separatists it backs.

Merkel indicated earlier this week that she favors putting more rebel leaders on the sanctions list but stopped short of advocating more economic sanctions against Moscow.

Asked in an interview with the state-owned news agency TASS, Putin said he "has not noticed" any between him and Merkel.

He added that in its policies, Russia is "guided by interests, not personal sympathies or antipathies."