Ed Sheeran has hit out at the Backstreet Boys for playing new music at their reunion shows instead of classic hits.

The 'Sing' hitmaker slammed the 90s US boyband - made up of Brian Littrell, A.J McLean, Howie Dorough, Nick Carter and Kevin Richardson - for letting their fans down by performing new material during their 20th Anniversary Tour.

Ed told The Sun newspaper: ''I study how other people perform and that is unacceptable, as the Backstreet Boys have so many hits. Do not do that ever again, that is not fair.''

After hearing frontman Brian also played an acoustic set to open the band's show, the 23-year-old singer was particularly upset.

He said: ''No mate - do that if you have your own gig, Brian. I played the Royal Albert Hall and did two new songs, but I know that's what people want. The Backstreet Boys, what are they doing? Play your hits.

''If you're a proper muso and people go to your gigs to witness your musicianship, a la Eric Clapton and Stevie Ray Vaughan, do it. But if you're a pop star play your pop songs.''

Ed insists he is a fan of the 'I Want It That Way' hitmakers, but claims he wouldn't go to a gig if they didn't play the hits.

He added: ''That would really annoy me. Like when I saw Justin Timberlake, it was one of the best shows I ever watched as it was back-to-back hits, people need to do that much more.

''I went to see Paul McCartney and I knew every song, hit after hit.''

Meanwhile, the Backstreet Boys will kick off the North American leg of their tour on May 3, followed by another European leg a month later before wrapping up the gigs in Poland in July.