Immediately after his news conference alongside Russian President Vladimir Putin, President Donald Trump's mood was buoyant, people familiar with the matter said.

He walked off stage in Helsinki with little inkling his remarks would cause the firestorm they did, and was instead enthusiastic about what he felt was a successful summit.

By the time he'd returned to the White House just before 10 p.m. ET on Monday, however, his mood had soured.

Predictably, the President was upset when he saw negative coverage of the summit airing on television aboard Air Force One. It was clear he was getting little support, even from the usual places.

He vented to aides traveling with him, including new communications chief Bill Shine and policy aide Stephen Miller. First lady Melania Trump was also aboard and was involved in some of the discussions, but not all of them, the people familiar with the matter said.