Kim Kardashian has reportedly warned Kendall Jenner not to fall in love with Harry Styles.

The reality TV star and her sisters, Kourtney and Khloe, have all told their stepsister not to get too involved with the One Direction hunk - who has been romantically linked with a string of women including Taylor Swift, Cara Delevingne and Natalie Imbruglia since finding fame - but she has told them it is too late for their interference.

A source said: ''Kim, Kourtney and Khloe are super worried about baby sis, and keep warning her, 'Don't fall in love with Harry, he's going to break your heart'. But it's too late, Kendall told them, 'I'm already madly in love with Harry' ''

Kendall, 18, and Harry, 19, were introduced in November and have since been on romantic dates in New York and London, as well as a ski trip in California, and while the Kardashian sisters are worried, their mother and manager to all the girls, Kris Jenner, is happy about the romance.

The source added to National Enquirer magazine: ''Kris just loves all the publicity about Harry and Kendall, and absolutely flipped about Kendall's idea to feature Harry on several episodes of 'Keeping Up with the Kardashians'. Even though Harry's been reported as saying he won't go on the show, she's still hoping Kendall might somehow sweet talk her beau into doing the show.''