Well, if you come to sign a deal, don't come under false pretenses and then bring things up at the last minute in the Oval Office at a press conference when you have had days to do so. He's playing games. Further, dont' get to try to get the President to bad mouth the aggressor when he is trying to get him to the negotiating table, for that would probably make Russia and/or Putin get up and walk out. That isn't generally how it works.