BENOUVILLE, France (REUTERS) - US President Barack Obama urged Russia's Vladimir Putin during a brief informal meeting in France on Friday to seize the opportunity to ease tensions in Ukraine after the election of MR Petro Poroshenko as president, a White House official said.

"President Obama made clear that de-escalation depends upon Russia recogniSing President-elect Poroshenko as the legitimate leader of Ukraine, ceasing support for separatists in eastern Ukraine, and stopping the provision of arms and material across the border," deputy national security adviser Ben Rhodes told reporters with MR Obama for D-Day commemorations in France.

"If Russia does take this opportunity to recogniSe and work with the new government in Kiev, President Obama indicated that there could be openings to reduce tensions," he added.