5 Seconds of Summer are to work with Motley Crue's Nikki Sixx.

The 56-year-old bassist revealed the news on Twitter while congratulating the punk-pop band - featuring Michael Clifford, Luke Hemmings, Calum Hood and Ashton Irwin - for winning the Best Fan Army accolade at the iHeartRadioAwards in Los Angeles.

He wrote: ''Congrats @5sos on your award. Nice Crüe shirt too.See yah next week for some lyric writing. (sic)''

The band topped the US charts and reached number two in the UK with their eponymous debut album last year, and are hoping to have their new record out before the end of 2015, despite the fact they will be on the road with their 'Rock Out With Your Socks Out Tour' until mid-September.

Guitarist Michael explained: ''We've written most of it, and we're recording it now. We'll release it when it's right, whether it's on the tour or at the end of the tour.

''New music will definitely be out this year.''

As well as working with the Motley Crue songwriter on the album, the group have also employed the talents of Katy Perry collaborator Bonnie McKee, and 'Amnesia' hitmakers Joel and Benji Madden.

Speaking about The Madden Brothers - who they previously worked with on their debut - Luke told Billboard: ''They've had a big role in the album this time, even more so than the last album.

''It's been really fun. We really look up to them, their whole movement as a band. It's amazing they're on board with us. They're great dudes.''