Sir Paul McCartney has announced that he and his wife Heather Mills are seeking a trial separation from each other.

The pair's four-year marriage is in trouble following a number of harsh rows apparently centering around Heather's attempts to raise the profile of her animal rights campaigns.

This Is London quote one source as saying: "Paul hasn't come to this decision lightly, but felt things couldn't carry on as they were.

"He and Heather were getting on so badly it became impossible for them to sleep under the same roof. It's terribly sad for them but nobody has entirely lost hope."

If the couple were to divorce, it is thought Heather, 38, could claim around £200m of Sir Paul McCartney's £825m fortune. The couple did not sign a prenuptial agreement.