Before he started the part he was called for, the 74 years old actor shouted on the stage, "I'm just going to say one thing".
"It's no longer down with Trump, it's f-- Trump!"
It was hardly the first time that De Niro, who was born in NY and lives in the city, attacked fellow New Yorker Trump.
The Oscar victor actor added, "It's no longer 'down with Trump.' It's 'f**k Trump!'"
Trump thinks Kim will get rid of nukes 'virtually immediately'
The Blast spoke with Mark Castaldo, founder of the award-winning Destiny Pictures production company in Los Angeles. The video was also broadcast during a press conference, and Trump bragged to reporters that he thinks Kim loved it.
"I just want to make a note of apology for the idiotic behaviour of my president", De Niro said in Toronto while attending a ground-breaking ceremony for a new luxury restaurant and hotel complex.
De Niro was much more candid at the Tony Awards on Sunday night, earning a standing ovation for expletives aimed at the USA president. De Niro said he'd be happy to accept.
American viewers watching the Tonys at home only heard silence - the broadcast on CBS bleeped De Niro's expletive-heavy intro - but they saw the audience's largely enthusiastic reaction, the Associated Press reported. "Boy, do we need that now".
Robert De Niro seemed to be sending a message on behalf of Broadway. Kushner went even further, calling Trump's presidency "the Hitler mistake" that put a "borderline psychotic narcissist in the White House". "Who's gonna argue with him?"
ABC's talk show The View's co-host Meghan McCain also critiqued De Niro: "When you're talking about how Trump is degrading our national discourse with his language, this is not the way to combat Trump, it only helps him".