Some critics have praised Angelina Jolie's performance as renowned opera singer Maria Callas, saying she "soars into the Oscars race", but others were less keen, calling the film "wearily flat".

The actress's new biopic, titled Maria, had its world premiere at the Venice Film Festival on Thursday.

Jada Yuan wrote in The Washington Post that Jolie was "almost a sure thing to get a best actress nomination" for next year's Academy Awards.

But in The Times, Kevin Maher called her "a pale imitation of an opera star", adding: "This is a film fed by, and consistently cutting to, the operas that defined its subject.

"Yet there is not a single moment that is emotionally operatic. It is wilfully, wearily flat."

Nate Jones wrote in Vulture that director Pablo Larraín’s film had been "pegged by Oscar-watchers as a title to watch out for".

"A film about opera legend Maria Callas... set in the final weeks of her life... starring Angelina Jolie who’s making her grand return to screen after years away from the spotlight.

"Singing, stars, drugs, death, comebacks - if this film checked any more boxes, it'd be a tax form."

The Daily Mail's Brian Viner gave the film two stars, but praised Jolie's performance.

He said the actress "spends most of Maria’s two hours as a whining, self-pitying, endlessly needy victim... all that said, she gives one of the performances of her career.

"This might be a flawed depiction of Callas but not by her; wearing enough mascara to sink one of Onassis's ships she is completely believable in the role and even does some of her own warbling alongside some top-class lip-synching to the real Callas, having reportedly trained for seven months until she was ready to perform in public for the first time.

"Admittedly I'm no expert but I couldn't tell the difference."

The film is widely seen as the third in a trilogy of films by Larrain, who also directed 2016's Jackie, about Jacqueline Kennedy Onassis, and 2021's Spencer, about Princess Diana. Maria was written by Steven Knight, who also penned Spencer and hit BBC TV series Peaky Blinders.

Larrain told reporters in Venice: "Having the chance to combine my two most deep and personal passions, cinema and opera, has been a long-awaited dream," according to the Daily Mail.

"To do this with Angelina, a supremely brave and curious artist, is a fascinating opportunity. A true gift."

Speaking at the press conference in Venice, Jolie said she was "terribly nervous" about singing.

"When you work with Pablo, you can’t do anything by half," the star said.

She was moved to tears during a long standing ovation at the festival, according to CNN.

When asked about her personal connection with the singer, the actress responded: "Well, there's a lot I won't say in this room, that you probably know or assume," People reported.

"I think the way I related to her may be a surprise - [it was] probably the part of her that's extremely soft and doesn’t have room in the world to be as soft as she truly was, and as emotionally open as she truly was.

"I share her vulnerability more than anything."

Jolie's personal life has regularly made headline news, including her divorce from actor Brad Pitt, which was announced in 2016.