LONDON (AP) -- British singer Amy Winehouse is canceling part of her European tour after the singer was booed for strange behavior during a concert in Serbia.
A Winehouse spokesman said she will be canceling an appearance in Istanbul on Monday and in Athens on Wednesday.
The spokesman said Sunday that Winehouse would like to say sorry to fans expecting to see her, but "feels that this is the right thing to do."
He added that she will return home after agreeing with management that "she cannot perform to the best of her ability."
The singer, who has publicly struggled with drugs and alcohol, was jeered late Saturday as she performed in Serbia's capital Belgrade. She stumbled onto the stage, mumbled through her songs and sometimes wandered off.
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