Their unforgettable performance as on-screen couple Rose and Jack in Titanic catapulted Kate Winslet and Leonardo DiCaprio to global stardom back in the 90's.
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Now, over 20 years later, both actors are still Hollywood heavyweights, with Kate garnering Oscar buzz for the upcoming romantic period drama Ammonite.
But what do you know about the stars' friendship today? Keep reading for everything Kate has said about her relationship with Leo over the years...
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When Kate and Leo first met on the set of the blockbuster James Cameron movie, she was 21 years old, and he was 22. Thanks to their undeniable on-screen chemistry, rumours about a possible romance between the two young actors soon began to swirl.
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However, Kate denied there was anything more than friendship between the pair in a Rolling Stone interview following the movie's release. "Just the notion of that was insane it would have been absolutely like incest," she said, revealing that the two would often read the gossip stories about themselves and laugh.
Kate and Leo set rumours flying thanks to their chemistry in Titanic
Kate later opened up further about "disappointing" fans with their strictly platonic relationship, saying: "I think the reason that friendship works is because there was never any romantic thing.
"It's so disappointing for people to hear that because, in the soap opera of the Kate and Leo story, we fell in love at first sight and had a million snogs, but we never did," she told Marie Claire.
Despite not growing close in a romantic way, the two have remained in each others' lives, and Leo even walked Kate down the aisle back in 2012. The actress, who has been married twice before, wed Edward Abel Smith, formerly known as Ned Rocknroll, in an intimate ceremony in New York that was only attended by the couple's closest friends.
Kate and Leo at the 1997 premiere for Titanic
When Kate's mother died of ovarian cancer just a few years later, the two co-stars put their heads together and used their friendship to achieve something incredible. By auctioning off a private dinner with 'Jack and Rose', they managed to raise $1.35million and fund a British woman's cancer treatment, saving her life.
Their friendship is still going strong today, with Kate recently revealing that the pair like to crack each other up by "quoting the odd Titanic line back and forth to each other".
The two stars are still close friends today
As for Leo, he opened up about his 20 plus year friendship with the British beauty in an interview with Oprah Winfrey. "In a lot of ways, Kate and I have really grown up in this industry together; we've been a support mechanism for each other for such a long period of time. We've been there for each other and helped guide each other."
However, he couldn't help but tease all those hopeful fans out there when asked by an audience member who his favourite on-screen kiss was. "I'm gonna go with Kate Winslet. Good old, classic…" he said.
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