Mark Ronson has played a tribute concert to Amy Winehouse a day after he attended the funeral of the 27-year-old singer.

Despite some public spats, the two Jewish stars were close and Mr Ronson produced the singer's second album Back To Black.

At a show at the Greenwich Summer Sessions, he spoke of her "genius" and said it had been a difficult week. He opened his set with a version of Valerie, the Zutons' song that Ms Winehouse covered to critical acclaim.

Mr Ronson, who said on Sunday that Ms Winehouse was like a sister to him, told the crowd: "I went to her service yesterday and a rabbi said, 'A person's life is measured in deeds, not years', hers was pretty f****** special.

"Amy Winehouse was a genius and has made more brilliant music than I'll ever make."

Although a post-mortem has not yet revealed the cause of the singer's death, the Sun reported that her parents thought it might have been giving up alcohol.

The newspaper quoted a source saying: "Abstinence gave her body such a fright they thought it was eventually the cause of her death."