Perry, Brand marriage on the rocks?

Singer Katy Perry and her husband of 14 months, British comedian Russell Brand, spent Christmas Day apart, adding fuel to speculation of discord in their marriage.

Following what Us Weekly Wednesday characterized as a heated, profanity-filled argument, Perry -- who had planned to fly her family by private jet to London, Brand's hometown, for the holidays -- stayed with friends in Hawaii, where she was photographed swimming without her wedding ring.

Among her group, said People magazine, was jewelry designer Markus Molinari, a close friend who has attended industry events with her.

People said Perry, 27, and Brand, 36, appeared to be happy when they arrived at the Hawaiian island of Kauai before Christmas weekend. But by Christmas Day, said Us, Brand was in England, spending time with a buddy in a pub in Coverack, Cornwall.

Brand later attended a charity swim with his comedian and TV-presenter friend David Baddiel, said Britain's Daily Mail. The paper said he was also spotted at Winter Wonderland in London's Hyde Park Tuesday.

Rumors of an impending breakup have dogged the couple for months.

When asked about the possibility on "The Ellen DeGeneres Show" earlier this month, Brand joked, "What?! She should have told me!" He went on to say, "I've treated the whole Internet now as a wicked little liar. I am really happily married," and added, "Perpetually, until death do us part was the pledge. I'm still alive."

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Perry's single "Firework" has been nominated for record of the year and best pop solo performance at the 54th Grammy Awards in February.

Brand next appears in the film adaptation of the Broadway jukebox musical "Rock of Ages," playing Lonny Barnett, the story's narrator.