President Barack Obama said on Wednesday 19 December it is in the worlds interest for the United States and Russia to have a constructive relationship, but Russias return to an adversarial spirit under President Vladimir Putin made that difficult. I think that it is in Americas interest, in the worlds interest, that we have a constructive relationship with Russia, Obama said in a news conference on Wednesday (January 18) two days before handing over the presidency to Donald Trump. Obama also stressed sanctions on Russia were because of encroachments on Ukraines sovereignty and independence.