The Vamps hope Demi Lovato will help them to crack America.

The 21-year-old star features on the British boy band's new track 'Somebody To You' and Bradley Simpson has confessed he and his bandmates are hoping her contribution may win them more fans stateside.

He said: ''I think it definitely helped us. To have such a superstar on the track is amazing. I think it'll help us hopefully in America as well to reach new audiences.''

The 19-year-old singer also revealed that he hopes he and the rest of The Vamps - Connor Ball, Tristan Evans and Connor McVey - will be able to return the favour to the 'Skyscraper' hitmaker.

Speaking to MTV News, he added: ''And hopefully, in some kind of way, we've helped her as well to open her up to our fans, who probably will have heard of her, but will now get to experience the amazing Demi Lovato.''

The foursome also revealed how the collaboration came about with Connor joking that she ''appeared out of the blue''.

He added: ''Nah, we were just working with the same producers as her and she came in and did her parts the week after we recorded which was very lovely of her.''

Simpson continued: ''We always knew we wanted a feature on that song and Demi nailed it.''