Los Angeles, Dec 22 (IANS): Hollywood actress Jennifer Aniston has taken off her wedding ring, fuelling speculation that her marriage to Brad Pitt is in trouble.

The former "Friends" star was seen wearing the wedding ring when she left London's Dorchester Hotel, where the couple had been staying during Pitt's promotional tour for the film "Ocean's Twelve", reported the Internet Media Database.

But she reportedly removed it when she landed at the Los Angeles airport Sunday.

Rumours about the relationship deteriorating were first sparked during the filming of "Mr. And Mrs. Smith" this summer when Pitt was romantically linked to his co-star Angelina Jolie.

Aniston added to speculations by cancelling Pitt's 41st birthday party she'd agreed to host, weeks after reports that she refused to have his first child.

But last week, there were reports of Pitt planning to fly out with Anniston to New York, in between his "Ocean's Twelve" promotional tour in London, to be by her side while she attended the funeral of a close friend.

"Jennifer never takes her ring off, it's her absolute pride and joy. It is very unusual that she wasn't wearing it," a source was quoted as saying.