Angelina Jolie was grateful for the support of director Pablo Larrain as she learned opera for 'Maria'.

The 49-year-old star plays soprano Maria Callas in the new biopic and was thankful that the 'Spencer' filmmaker understood how much effort was needed for the part.

Speaking to Variety about the difficulties of performing opera, Angelina said: "It wasn't easy. I was fortunate to have a director who truly understood and respected opera. He knew how much work was required and assembled a team around me to teach me.

"He made sure I had the classes I needed and gave me the space to practice. From the beginning, he understood that I needed extra time to prepare, and he always supported my transformation process."

Angelia explained that it was "daunting" to take on the role of Callas but was delighted to be working with the Chilean filmmaker who she has long admired.

The 'Eternals' star said: "You always hope to work with directors you've admired, and I've wanted to work with Pablo for a while. It is a gift to take on something like this, knowing you're in good hands and can push yourself to the edge because they'll catch you.

"Her music was daunting, but it's good to feel scared. As an artist, being so challenged that you're unsure if you can do it is a great feeling."

The biopic received an eight-minute standing ovation when it premiered at the Venice Film Festival last week and Jolie explained that she spent the time reflecting on the legacy of the opera diva – who passed away aged just 53 after spending her final years living in isolation after her partner Aristotle Onassis left her for Jackie Kennedy.

She said: "I thought about her a lot in that moment. It's strange when you feel so close to this real human being. I know that applause was for her life.

"Often, we don't, as artists, know if our work resonates, or we don't expect kindness. You walk out expecting not to be supported or not to connect. But 'Maria' did."