Prime Minister Gordon Brown has revealed that he gave Nelson Mandela a brief history of Amy Winehouse when the pair met during the summer.
Winehouse was one of a number of musicians at Mr Mandela's 90th birthday celebrations in London's Hyde Park.
As well as performing her own material, the singer played a cover of 'Free Nelson Mandela' – but re-arranged the chorus to include the lines: “free my blakey, my fella”, in reference to her incarcerated husband, Blake Fielder-Civil.
Speaking to 100 members of campaign group the Peace Alliance this week, the Prime Minister said it was his job to tell Mr Mandela about Winehouse's history, including her husband's imprisonment.
Mr Brown said: "As he looked at the concert I had this responsibility of explaining to him, as she came on stage, who Amy Winehouse was. And so I was, um, it took a bit of time to tell the full story.
"Then Amy Winehouse was saying to her friends, 'You know, Nelson Mandela and my husband have a great deal in common - both of them have spent a great deal of time in prison'.
"And then when people were singing at the end that great song, Free Nelson Mandela, she was actually singing, 'Free Blakey My Fella'."
According to the Sun newspaper, Mr Brown's comments left members of the Peace Alliance “in stitches”.
“It was lovely to see another side of him and goes to show he has a great sense of humour,” a source added.
Fielder-Civil is currently serving a 27-month prison sentence after he pleaded guilty to assault and perverting the course of justice.
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