One Direction's Harry Styles Sings Karaoke With Alexa Chung And Pixie Geldof

The 'Gotta Be You' singer is believed to have sung 'Boyfriend' to celebrate Pixie's 22nd birthday.

One Direction star Harry Styles partied with model Pixie Geldof and presenter Alexa Chung on Monday as they enjoyed a night out singing karaoke together.

The 'What Makes You Beautiful' singer helped Bob Geldof's daughter Pixie celebrate her 22nd birthday (17th September) fresh from being pictured out at the Burberry catwalk show as part of London Fashion Week earlier in the evening.

Harry joined Pixie, Alexa and a number of friends at the Lucky Voice karaoke bar in London's Soho area, where the 'One Thing' star was said to have sung Justin Bieber's hit single 'Boyfriend', according to The Sun.

"Had the greatest birthday! Dinner, karaoke! then a late-night sing song by a piano!" Pixie tweeted after the birthday celebrations.

View a picture of Harry Styles and Alexa Chung below (Credit: PA):

Earlier in the evening Harry had watched model Cara Delevingne walk the catwalk for Burberry Prorsum, with whom he has been romantically linked in the past, and said afterwards she had looked "amazing" at the show.

Harry is set to join bandmates Liam Payne, Niall Horan, Louis Tomlinson and Zayn Malik tomorrow night (20th September) for their long awaited show at the Roundhouse in Camden, London for iTunes Festival 2012.

One Direction will release their brand new single 'Live While We're Young', the lead track from new album 'Take Me Home', on 30th September.