US singer Britney Spears is to play two concerts at the O2 arena in London next June - the only European shows on her forthcoming world tour. Tickets for the dates on 3 and 4 June will go on general sale on 5 December - although fans who register with her website can buy them 24 hours earlier. "It's going to be very special," said Rob Hallett of tour promoter AEG. The concert, he said, would take its theme from her latest album The Circus, which is released next week. "We're creating a musical circus," he said. "Expect to see jugglers, dancers, tattooed ladies and acrobats." According to the promoter, the concerts will be Spears' only dates in Europe "for the foreseeable future". Spears last performed in the UK in 2004 when her Onyx Hotel tour visited Birmingham, Glasgow, Belfast, Manchester and Wembley Arena in London. - BBC