The veteran actress had been approached to star as Aunt Emma in Martin Scorcese's 2013 flick, but had to turn down the gig because she was too "stoned" on prescription drugs to be able to work.
Explaining that she regrets missing out on the opportunity to appear alongside Leonardo DiCaprio in the movie, Andrews explained on Thursday's instalment of "Watch What Happens Live": "I had an operation. I'm a bionic woman. I have a titanium ankle."
"I was so truly stoned from all the drugs that I had to take just to take the pain away," the "Mary Poppins" actress added.
Despite admitting she "would've loved to do it," the star confessed she unfortunately "just wasn't ready" to return to work when filming for the project began.
The "Princess Diaries" actress also opened up about the possibility of a third movie in the popular franchise, admitting she "hasn't heard" anything about it but suggesting she'd love to take part.
"I think if it happens it will be lovely and if it doesn't I wouldn't have known about it," she said.