"I did what I could to encourage Russia to be a constructive member of the international community. After President Putin came back into the presidency, an escalating anti-American rhetoric and an approach to global affairs that seemed to be premised on the idea that whatever America is trying to do must be bad for Russia and so we want to try and counteract whatever they do - that return to an adversarial spirit that I think existed during the Cold War has made the relationship more difficult," Obama said.
"And it was hammered home when Russia went into Crimea and portions of Ukraine. The reason we imposed the sanctions was not because of nuclear weapons issues. It was because the independence and sovereignty of a country, Ukraine, had been encroached upon, by force, by Russia. That wasn't our judgment; that was the judgment of the entire international community.
"And Russia continues to occupy Ukrainian territory and meddle in Ukrainian affairs and support military surrogates who have violated basic international law and international norms. What I've said to the Russians is, as soon as you've stopped doing that the sanctions will be removed," the U.S. president said.