WARSAW, Poland (AP) — President Barack Obama says that in the aftermath of elections in Ukraine it is possible for the United States to rebuild trust with Russian President Vladimir Putin. But he says it will take some time and require Putin to pull back Russian troops from the Ukrainian border and use his influence to calm unrest in eastern Ukraine.

Obama says he has always had a businesslike relationship with Putin and that he has made it clear to him that the United States is not interested in threatening Russia. He says Russia has a legitimate interest in what happens along its borders.

Obama spoke during a joint news conference with Polish President Bronislaw Komorowski at the start of a week-long trip to Europe.

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