McBusted have been named as the headliners for British Summer Time 2014.
The group, made up of Mcfly and Busted, will close the first weekend of the festival in Hyde Park on Sunday 6 July.
American boyband The Backstreet Boys have also been confirmed on the line-up.
The second weekend will be headlined by Neil Young and Crazy Horse on July 12, with The National and Tom Odell also on the bill.
The announcement comes less than a month after McBusted confirmed they will embark on a UK arena tour next year.
During a video announcing their Hyde Park headline slot, Mcfly singer Tom Fletcher said: "This is going to be the biggest show of our lives. It's going to be the biggest show we've ever played. Potentially the biggest show we will ever play."
Drummer Harry Judd said: It's (McBusted) bigger that what Busted ever were and it's bigger than what McFly ever were. That's the weirdest thing."
Busted formed in 2002 while McFly's debut single Five Colours In Her Hair was released in March 2004.
McFly and Busted have 11 number one singles between them.
Tickets for the festival go on sale at 9am on Friday 13 December.
More acts for both weekends are set to be announced.
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