Troubled British singer Amy Winehouse on Sunday cancelled her appearances at festivals in Turkey and Greece after she was jeered at a show in Serbia when it appeared that she was too drunk to perform.
The soul-diva pulled out of the shows, which take place later this week, as she "cannot perform to the best of her ability", her spokesman said.
Winehouse, who has battled drug addiction and has reportedly received treatment for a drinking problem, mumbled her way through Saturday's set at Belgrade's Fortress festival before 20,000 disgruntled fans.
Many soon left the concert, calling the 27-year-old singer's performance a "scandal" and a "disaster".
During the 90 minute set, Winehouse left the stage twice, while many fans - some from neighbouring countries - booed and whistled as she tried to find a proper note, with her band trying to calm the crowd.
The multi-Grammy award winner apologised for pulling out of her appearances at the Kucuk Ciftlik Park festival in Istanbul and the Ejekt festival in Athens.
Her spokesman said: "Despite feeling sure that she wanted to fulfil these commitments, she has agreed with management that she cannot perform to the best of her ability and will return home.
"She would like to apologise to fans expecting to see her at the shows but feels that this is the right thing to do."
Winehouse reportedly ended an alcohol rehabilitation programme in London two weeks ago and local media reported that alcohol had been banned for the tour.Reuse content