Rites of Passage star Christian Slater has announced that he is set to walk down the aisle with his longtime girlfriend Brittany Lopez.

The 43-year-old actor broke the news during an appearance on US show Late Night With Jimmy Fallon on Wednesday.

Speaking about how he first met Lopez in Florida, Slater said: "I went down to Miami a couple years ago, stayed at this little place (resort) called Little Palm Island... and this girl came walking along with another lady, a slightly older lady. I was sitting in my usual spot, eating my oatmeal that morning... and this spot was famous for people proposing to each other... and next thing I know she gets down on one knee and proposes to this older lady...

"I thought I had just witnessed a nice lesbian engagement, so I was coming over to say congratulations, but it turns out it was her aunt and she was just trying to help her aunt capture the beauty and the romance of the moment. She was making a joke, and I witnessed it, and it intrigued me, and the next thing I know we were hanging out in the Everglades."

Slater was previously married to Ryan Haddon, the daughter of 1970s model Dayle Haddon. The couple have two children, Jaden Christopher and Eliana Sophia.