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MOSCOW, April 18 (Reuters) - Russia voiced disappointment on Friday with the U.S. assessment of an international deal to defuse the crisis in Ukraine, saying the threat of new sanctions against Moscow by Washington was "completely unacceptable".
The Foreign Ministry accused U.S. officials of seeking to whitewash what it said was the use of force by the Ukrainian government against protesters in the country's mainly Russian-speaking eastern provinces.
"American officials sounded ultimatums, and tried to threaten us with new sanctions, which is completely unacceptable," the ministry said in a statement.
Thursday's deal called among other things for all illegal armed groups to disarm and end occupations of public buildings in Ukraine's east. Armed pro-Russian separatists dismissed the accord, saying they were not bound by it.
President Barack Obama said the meeting in Geneva between Russia, Ukraine and Western powers was promising but that Washington and its allies were prepared to impose more sanctions on Russia if the situation fails to improve.
Moscow described Washington's stance as one-sided and said it was "disappointed" by its remarks after the talks, which seemed to offer the best hope of resolving a confrontation that has dragged relations to their lowest ebb since the Cold War.
"The blame for the Ukrainian crisis and its current aggravation is unreasonably being placed on Russia," the ministry said.
"The American side is once again stubbornly trying to whitewash the current actions of Kiev's authorities, who have embarked on a course for the violent suppression of protesters in the southeast who are expressing their legitimate indignation over the infringements of their rights."
(Reporting by Alissa de Carbonnel; Editing by Christian Lowe and Mark Heinrich)