A lack of film roles for actresses in their 50s is "a disaster" and the situation is unlikely to change, Dame Kristin Scott Thomas has said.
Speaking on BBC One's Andrew Marr Show, she said: "I won't bore you with all the stories of older women not getting jobs in film because it's so boring. But it's true. It's a disaster."
Asked why it was boring, she replied: "Because it's never going to change."
Dame Kristin, 54, will soon be seen in World War II drama Suite Francaise.
"Until the average lifespan is 150 years or something, I don't think women in their 50s are going to be considered at all viable," she added.
"I think that's what it is. Sorry."
In Suite Francaise, based on the novel by Irene Nemirovsky, Dame Kristin plays a French woman in 1940 whose daughter-in-law becomes involved with a German officer.
The Oscar-nominated actress was quoted last year as saying she was "stopping" making films because she was bored with playing similar roles and "cannot cope with another film".
But speaking to The Andrew Marr Show's stand-in host Sophie Raworth, she admitted she had recently been tempted by another movie.
"I'm very good at doing a certain type of thing," she said. "So people will always want you to do what you're good at - it's natural. And it just gets really boring.
"So I prefer to do something that is more exciting for me, that takes more risks. And, in taking more risks with directors or with characters, then you risk failure. That's the whole point.
"I've found recently that the films that I've done through choice, because they were so much more exciting, have not been successes.
"But it won't stop me from keeping doing them because I just enjoy it so much."
Dame Kristin is best known for roles in The English Patient, Gosford Park and Four Weddings and a Funeral.
She was nominated for a Bafta for playing John Lennon's Aunt Mimi in 2009's Nowhere Boy.
More recently, she played Ryan Gosling's mother in 2013 Only God Forgives, was seen as Dame Maggie Smith's daughter in My Old Lady, and appeared opposite Ralph Fiennes in The Invisible Woman.
She will also play the Queen on the London stage from April, taking over from Dame Helen Mirren in The Audience.
The play comes after she was made a dame in the Queen's New Year honours - which the actress described as "really thrilling".