In his calls with both Merkel and Poroshenko, Obama also expressed his sympathy for the mounting toll of the conflict in eastern Ukraine and his deep concern about the ongoing violence, particularly in and around Debaltseve.
Obama and Merkel are particularly concerned about the intense fighting in and around Debaltseve, the White House said, adding that they also agreed on the pressing need for all signatories to implement the ceasefire and protocol agreements reached at Minsk last September and reaffirmed by the Minsk Implementation Plan this week.
In another call with his Ukrainian counterpart, Obama emphasised the pressing need for all signatories to implement the ceasefire and protocol agreements reached at Minsk last September and reaffirmed by the Minsk Implementation Plan this week.
"They agreed to remain in close contact in the days ahead. Both leaders stressed the importance of establishing a lasting peace that respects Ukraine's sovereignty and unity," the statement said.
"Separately, the President congratulated Poroshenko on Ukraine reaching an agreement with the International Monetary Fund on an ambitious package of reforms that will help to stabilise Ukraine's economy and lay the groundwork for growth and prosperity," the White House said.