10/15/2008 at 01:45 AM EDT
and husband Guy Ritchie are ending their almost-eight-year marriage, a rep for the singer confirmed Wednesday.
"The main concern for Madonna and Guy are their children – the security of their children in all senses of the word and the wellbeing of their children," rep Liz Rosenberg tells PEOPLE. "That's the priority for both of them moving forward. It's a sad situation."
The former couple
, who have Rocco, 8, and David, 3, together and Madonna's 12-year-old daughter Lourdes with ex Carlos Leon, announced their divorce in a statement.
"Madonna and Guy Ritchie have agreed to divorce after seven-and-a-half years of marriage. They have both requested that the media maintain respect for their family at this difficult time," says the statement.
The statement says they have not agreed to a settlement.
"The judgment of the court would be to try and assess what they came in with and divide what they built up fairly equally," said David Allison, a lawyer with Family Law in Partnership, a London firm, told the Associated Press.
In a front page story Wednesday, Britain's Sun
newspaper claimed that the couple will be issuing a statement "imminently" on the demise of their often tempestuous relationship, which has been the subject of much speculation
in recent months.
Madonna, 50, is in the midst of her Sticky and Sweet tour
and is set to play Boston Wednesday night. Ritchie, 40, was believed to be on the U.K. set of his latest film, Sherlock Holmes
Reached at their home, his family declined to comment.
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