De Niro says Hollywood worried about 'wrath of Trump'
The 81-year-old, one of the most outspoken critics of the American leader, used his Tuesday evening speech to condemn him again, calling him a "philistine".
"They have big businesses, they have to worry about the wrath of Trump, and that's where they have to make a decision: do I succumb to that or do I say no?" he told AFP.
But he cited as an inspiration the example of some US universities and legal firms who have stood up to attempts from Trump's administration to cow them.
"It's important, because other people pick that up, they see that they're fighting, it gives them strength to fight, and they're inspired by that," he added.
"They say it is possible... that's what America is about."
After accepting an honorary Palme d'Or on Tuesday evening for his contribution to cinema, the "Taxi Driver" star called for resistance against Trump's agenda.
As well as calling the president a "philistine", De Niro slammed his desire to implement 100-percent tariffs on films "produced in foreign lands".
"You can't have apathy, you can't have silence," De Niro said on Wednesday.
"People have to speak up and they have to take chances and risk being harassed. You just can't let the bully win, period."
Documentary film
De Niro also revealed Wednesday that he has been working on a new personal film project with New York-based French artist JR, best known for his huge photographic collages.
The film will be an exploration of De Niro's family, particularly his father, a painter, and the actor has opened up his family archives including abundant family videos.
"I don't know where we'll go," he told an audience during an interview with JR in Cannes. "There's no time limit, as far as I'm concerned."
The pair revealed some of the first images of their work, which include huge photos of De Niro's father and a sequence in which De Niro can be seen lying on one of them while travelling on a barge in New York's harbour.
It also features an appearance from Martin Scorsese, who directed De Niro in some of his best-known movies including "Goodfellas" and "Raging Bull".
The film also sees De Niro reflect on his life and twilight years.
Asked if he was afraid of death, he replied: "I don't have a choice, so you might as well not be afraid of it."