Al Pacino follows this mantra on every acting job

Al Pacino, Martin Scorsese and Robert De Niro attend "The Irishman" International Premiere and Closing Gala during the 63rd BFI London Film Festival
Mike Marsland/WireImage

Even after a movie career spanning half a century, legendary Hollywood actor Al Pacino says he still suffers from imposter syndrome.

"Sometimes I feel I know nothing about acting," he said in a recent interview with a panel of journalists, featured in U.K. newspaper The Guardian, but added these fears disappeared once he began to prepare for a new role.

"That's what's exciting for me. A new character," he said, citing a mantra that he often repeated — "Desire is more motivating than talent."

"I've seen people with great desire take it through," Pacino said, explaining that it has always been a case of "feeling this new character, this new person, this new story."

Although he admitted it was possible to go for long periods without feeling inspired by a role, Pacino said he was always on the lookout for one he could "really connect to."

Pacino was sat beside fellow Hollywood legend Robert De Niro, who he has reunited with for Martin Scorsese's mob epic "The Irishman," out this month.

De Niro's film career has also stretched over five decades and followed a similar course to Pacino's, with the two starring in a movie together for the first time in the second installment of "The Godfather" trilogy in 1974.

Reflecting on his career, De Niro said that while acting was "different" after all this time, he still liked it "just as much."

Pacino said he met De Niro in 1968 and they then "connected from time to time," finding they had shared similar experiences.

While Pacino said they don't see each other very much, they are "really close" and their friendship had "helped each other throughout life."

The "Irishman" is actually the first Scorsese film which Pacino has starred in, despite both having worked with De Niro a number of times.

"Like everything in this business, if you've been in it for a while, you realize that things get started, but then they go in different places and they don't always culminate in a film," said Pacino.

"A couple of times, Marty and I were going to do something together, then they slip away."