U.S. Vice President Joseph Biden in separate telephone conversations with President of Ukraine Petro Poroshenko and Prime Minister Arseniy Yatseniuk called on the politicians to unite over the ruling coalition, the White House has reported.

"He urged Ukraine’s leadership to unite and rebuild popular trust around a strong governing coalition and reform program, and to accelerate Ukraine's efforts to fight corruption, strengthen justice and the rule of law, and fulfill its IMF requirements," reads a statement.

The vice president also reiterated the importance of Minsk implementation by all sides "as the best way forward for resolving the conflict." During the conversation the Ukrainian leaders noted the continued failure by Russia and combined Russian-separatist forces to comply with their ceasefire obligations and allow the OSCE full access to the areas under their de facto control.