"I'm gonna say one thing: f- Trump!" he said as USA censors bleeped out his expletives targeting the president.
The legendary actor dropped the f-bomb while introducing Bruce Springsteen, who won a special Tony for Springsteen on Broadway and performed "My Hometown" at the show honoring the best of Broadway. "It's no longer just 'Down With Trump; it's, 'F-k Trump". "Boy, do we need that now!"
Spicer said De Niro's comments were unsuitable for prime-time television and represents "exactly what's going on" between the American people and Hollywood.
He went on to argue that people should be upset about Trump's rhetoric if they were angry about De Niro's.
The Tony Awards show was seen by some six million Americans a year ago.
The comment was such a hit with the awards show attendees that the actor then repeated the message again.
Warning: Language may be offensive in the video below.
De Niro's outburst was one of several political moments during the 72nd Annual Tony Awards. "When you see celebrities say I hope the economy bottoms out to get rid of Trump, I think that helps Trump". After leaving the summit, Trump quickly reneged on a joint communique after Trudeau reiterated to reporters that USA tariffs on Canada that site national security as a rationale are "insulting" to Canadians.