One Direction has signed a lucrative three year deal to "stick together" for at least three more years. The boys - Harry Styles, Niall Horan, Zayn Malik, Liam Payne and Louis Tomlinson - are in line for a huge payday in what appears to be a move from their record label to thwart any thoughts of solo careers.

Though any side projects would probably be released under Syco Records, Simon Cowell is keen to keep the boys together as a five-piece given they're now regarded as the biggest boy-band in the world. A source told The Sun, "It's a really clever contract that the boys have signed up to. It means they have a real incentive to tough it out and stick together. The formal length is for 36 months and an album a year - but the clever part is they get the big pay day after the three years." It seems an intentional move by Syco Records to stop the likes of Harry Styles going solo - the band's talisman and most popular member by some distance. It's not difficult to envisage the cheeky frontman filling a Robbie Williams-size hole in the pop world in a couple of years' time, though for the time being, he's contracted to focus on One Direction. The insider said, "If one of them walks away before then, then all five miss out on the money. They don't miss out on a few quid either, we are talking millions.They all get on really well, but it would be the kind of deal that would see them through the worst aggro possible."

Last year, the group managed to crack the notoriously tough U.S. market, becoming the first British group in American chart history to enter at No.1 with a debut album.

Watch One Direction Getting A Hero's Welcome In New York: