Madonna and Guy Ritchie's marriage is far from perfect, according to the pop star's brother.

Christopher Ciccone said this could be due to the contrasting progress of the ambitious pair's careers.

Speaking on GMTV, he said: "They are two very ambitious and creative people - so it has to be difficult."

Promoting his new book on the singer, the dancer said the couple's marriage is "not as good as (it) could be."

"Her career continues its gentle glide up but Guy's has gotten a little bit stale," he said.

Ciccone said being married to his 49-year-old sister would be "next to impossible".

He declined to say whether the relationship is in trouble following weeks of media reports and a denial Madonna's spokeswoman that they are consulting divorce lawyers.

However, Ciccone added: "It has to be difficult, when everyone in the world is saying you are about to get divorced - it's like being told you are fat - eventually you start to think you are."

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