John Lithgow reacts to controversy as he confirms Dumbledore role in Harry Potter

"It came as a total surprise to me," Lithgow told the publication. "I just got the phone call up at the Sundance Film Festival for yet another film, and it was not an easy decision because it's going to define me for the last chapter of my life, I'm afraid. But I'm very excited."

He noted that people are "turning their attention back to Harry Potter", which is why it had been "such a hard decision".

Lithgow, who is now 79 years old, added: "I'll be about 87 years old at the wrap party, but I've said yes."

While Lithgow has seemingly self-confirmed the casting, HBO is yet to officially announce his role, with a spokesperson telling Screen Rant: "We appreciate that such a high-profile series will draw a lot of rumour and speculation. As we make our way through pre-production, we will only confirm details as we finalise deals."

In an interview with Collider, Lithgow described the project as "a wonderful winding down role", and is "really excited about it" as he wants to do it and the fans "justice".

As he steps into the role, Lithgow confirmed to the publication he would be adopting an English accent: "[He's] certainly an Englishman. In fact, there’s a good deal of controversy that an American has been hired to play him. He’s such an icon. I’m half-English."

He continued: "I’ve just played Roald Dahl. I’ve played Winston Churchill. I’ll spend some time with a dialect coach, don’t worry about that.

"But no, I mean, Dumbledore couldn’t possibly be anything other than English. I just have to do my best. The wonderful thing is, I was welcomed by every English actor I worked with on The Crown. They had far more confidence in me and my Englishness than I did myself."

No other cast members have been confirmed, but some recent rumours have been sending fans into overdrive with equal excitement and hesitation as the seven books make their way to TV screens.

Just last year, The Hollywood Reporter claimed that The Lazarus Project actor Paapa Essiedu was in negotiations to play Professor Severus Snape, while Deadline reported that Sharon Horgan and Rachel Weisz were in the running to play Minerva McGonagall, with Brett Goldstein reportedly being linked to the role of Rubeus Hagrid.

As for a return of the film's original stars Daniel Radcliffe, Emma Watson or Rupert Grint, it seems unlikely, with Radcliffe previously ComicBook.com he has no plans to make an appearance.

He said: "My understanding is that they’re trying to very much start fresh, and I'm sure whoever is making them will want to make their own mark on it and probably not want to have to figure out how to get old Harry to cameo in this somewhere."

He continued: "So I'm definitely not seeking it out in any way… but I do wish them, obviously, all the luck in the world, and I'm very excited to have that torch passed. But I don't think it needs me to physically pass it."

The Harry Potter series will stream on Max.

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