Los Angeles, Sep 14 (IANS): Singer Dionne Warwick has hilariously mocked actor Leonardo DiCaprio's alleged relationship rule. The 81-year-old said that the 'Titanic' star doesn't know what he is missing with his supposed "25-year rule".

The 'Walk on By' songstress added it was the actor's loss he has form for dating women who are no older than 25.

She tweeted on Wednesday, September 14, "I just heard about Leonardo DiCaprio's 25 year rule. His loss. You don't know what you're missing."

The mother-of-two's message to her 608,000-plus followers quickly racked up almost 700 comments, with many praising Warwick as a "legend", reports aceshowbiz.com.

It comes as DiCaprio, 47, is back on the market after it emerged in August he had quietly split from his girlfriend, model Camila Morrone, a few months after she turned 25. Insiders said the pair grew apart after seven years, and called it a day earlier this summer.

A source last month told The Sun, "Leo and Camila ended their relationship over the summer. There are no bad feelings between them. It just came to a natural conclusion."

DiCaprio hasn't previously publicly dated a woman over 25, with his exes Gisele Bundchen, Bar Refaeli and Blake Lively not being over that age when they were together.

Morrone previously hit back when quizzed about their 22-year age gap, saying people should be free to date whoever they want without question.

She said during their relationship she was regularly mocked by trolls, including one who predicted her relationship with 'The Wolf of Wall Street' Oscar-winner would be "over when you're 25."

Morrone said: "There's so many relationships in Hollywood, and in the history of the world, where people have large age gaps. I just think anyone should be able to date who they want to date."