The couple - who this week have been dogged by reports their marriage is on the verge of collapsing - left their children, Lourdes, 11, Rocco, seven and two-year-old David with a nanny while they visited Milan at the end of last week.

However, the pair reportedly slept in separate rooms and are said to have spent very little time together.

A source close to the couple told Britain's The Sun newspaper: "They had completely separate rooms, schedules, everything. It was all very well organized but it's not a marriage the way most people understand it."

"They have this attitude like, 'We're not really a couple but we're friends and we love each other and raise our kids.' But the truth is they annoy each other, don't agree on anything, don't see each other or live 'together' as they did."

Madonna, 49, used the trip to visit fashion designers to source costumes for her forthcoming world tour, while Guy, 39, was working on a new commercial with actor George Clooney.

It was reported yesterday that Madonna had hired Fiona Shackleton, the lawyer who represented Sir Paul McCartney in his split from Heather Mills, to handle her and Guy's alleged divorce. A spokesperson for the singer has refused to comment on the claims.