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President Barack Obama says "it's too early to tell" how serious reports are of a cease-fire between Russia and eastern Ukraine.
Obama says the US has consistently supported efforts by Ukrainian President Petro Poroshenko to achieve a meaningful cease-fire that could lead to a political settlement after months of conflict between the countries.
Poroshenko's office today said that he and Russian President Vladimir Putin have reached agreement on a cease-fire in eastern Ukraine, where Russian-backed separatists have spent months battling the government in Kiev.
Today's statement says mutual understanding was reached. It provided no details.
Obama says no realistic settlement can be achieved if Russia continues to send tanks and troops into Ukraine under the guise of separatists.
Obama commented at a news conference in Estonia.
