AMY Winehouse has cancelled upcoming dates of her European comeback tour after being booed and jeered at a gig in Serbia. A spokesman for the troubled Rehab singer confirmed she would not be performing her next two gigs in Istanbul and Athens this week: 'Despite feeling 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 this is the right thing to do. It is yet to be confirmed as to whether the rest of the tour will go ahead as planned. Winehouse was performing on Saturday in Serbian capital Belgrade when she was booed and jeered at by fans. It was the first of 12 gigs across Europe for the singer. Fans said the 27-year-old took to the stage an hour late and was slurring her words as she stumbled around. She performed 'barely recognisable versions of her hits Back to Black and Valerie, clung on to her band members and was even seen throwing her shoes into the crowd. Metro