Elton John and Tom Odell join iTunes Festival line-up
Elton John is set to play at the iTunes Festival in London despite being diagnosed with appendicitis.
Doctors advised the singer to cancel forthcoming shows from his current tour.
This included his Hyde Park show as part of Barclaycard Presents British Summer Time Festival.
He is set to play at the iTunes the same night as Tom Odell.
A spokesman for Sir Elton said: "He is eager to be back on top form and return to play the remaining shows starting in early September 2013."
Other acts at announced as joining the iTunes line-up include Arctic Monkeys and John Legend.
Arctic Monkeys will headline a show on 9 September, to coincide with the release of their new album AM.
Robin Thicke will also be performing and revealed to Newsbeat that he would be in the UK on a mini-tour in the autumn before returning in the new year with Maroon 5.
Elton John said he was "proud to be in this year's iTunes Festival line-up".
He added: "For me, it's a real thrill to play for young audiences - they've got so much energy and they all seem to know my songs.
"The iTunes Festival evokes the spirit of memorable gigs at the Roundhouse over many years… and I should know, I've played a few there in my time."
Justin Timberlake, Jessie J, Queens of the Stone Age, Phoenix and Thirty Seconds To Mars have already been announced as performers at Camden's Roundhouse.
The current line-up is as follows:
Sigur Ros - 2 September
Paramore - 4
Rizzle Kicks - 5
Queens of The Stone Age - 6
Phoenix - 7
Arctic Monkeys - 9
Kings of Leon - 11
Elton John + Tom Odell - 12
Vampire Weekend + The Olms - 15
Jack Johnson + Bahamas - 16
Ludovico Einaudi - 17
Thirty Seconds to Mars - 18
Primal Scream - 20
Jessie J - 23
Pixies + No Ceremony - 25
John Legend + Robin Thicke - 28
Justin Timberlake - 29
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