AceShowbiz - Kings of Leon defied their record label bosses to debut new tracks from their next album at a show in London on Wednesday night, June 30. The rockers played in the U.K. capital's Hyde Park for 60,000 adoring fans and they took the opportunity to test out their previously unheard material.

Frontman Caleb Followill told the crowd, "Since we saw you guys last we went and made a record. That's what we put a lot of work into. Just yesterday some people at the record label got to hear a couple of songs from it. I don't know if they want us to play a bunch of new songs but I think 'f**k it' - were gonna do it!"

The band then launched into a series of tracks from their upcoming fifth studio album, as well as classics including "Sex on Fire" and "Use Somebody", according to NME.com. Caleb later became emotional onstage, revealing, "It's been one of the greatest experiences of my life. Thank you all very much. One of these days, when we're all fat and bald... or balder, and we're sitting in Tennessee telling all our kids about all the great things that happened to us, this is gonna be one of those."