WASHINGTON (AP) — Vice President Joe Biden is telling Ukraine’s leader that the U.S. and Europe are talking about imposing new costs on Russia for continuing to escalate the conflict in Ukraine.

Biden and Ukrainian President Petro Poroshenko spoke by phone on Tuesday. The White House says they discussed how Russia is continuing to support pro-Russian separatists and how the conflict has apparently escalated in recent days.

Poroshenko also told Biden that Ukraine tried to arrange a meeting including the separatists, Russia and Ukraine, facilitated by the Organization for Security and Cooperation in Europe. But the White House says Poroshenko told Biden that the separatists refused to attend.

The call comes as the U.S. is considering imposing unilateral sanctions without Europe. Countries in Europe have been reluctant to take tougher steps against Moscow.

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