Henry Winkler regrets turning down the chance to star in 'Grease'.

The 'Happy Days' legend didn't want to be typecast after rising to fame as Arthur 'Fonzie' Fonzarelli - also known as The Fonz - on the classic sitcom, and he thought the role of Danny Zuko was too similar.

He told CNNs Chris Wallace: "It was so bad that not only could I not find work, but I was sitting at my desk at Paramount and I literally thought, ‘Am I ever going to find anything with as much impact as the Fonz?'

“How will I know? Will anybody ever ask me? I’m not getting any offers.”

An offer did turn up, but Winkler snubbed the chance to play Danny, with the part eventually going to John Travolta.

Asked if he feels like a "damn fool" for rejecting 'Grease', Winkler said: "Yes. I am.

“I only realised years afterwards… I thought, ‘I’ve played the Fonz. I don’t wanna do it again, but it’s already happened, I’m already typecast.' ”

The 77-year-old actor - who currently appears with Bill Harder in HBO's 'Barry' - joked his life could have taken a very different turn if he'd accepted the offer.

He added: "I should’ve just shut up and had a really good time making that movie.

“Now, I go home, I say no, and I have a Diet Coke. John Travolta goes home, and has done the movie, and buys a plane.”

Despite his own legacy on the big and small screen, Winkler previously revealed he writes fan letters to other actors.

He explained: "I think if you see something it is so incredible, if you see a performance like Sam Rockwell as Fosse [in 'Fosse/Verdon'], you have to write a letter.

"If you see Patricia Arquette in 'Escape From Dannemora', you have to write a letter. I write fan letters."