Michael Douglas and Catherine Zeta-Jones separate

Updated 12:53 p.m. ET

Michael Douglas and wife Catherine Zeta-Jones have separated after nearly 13 years of marriage.

A spokeswoman for the actress told the Associated Press she and her husband "are taking some time apart to evaluate and work on their marriage."

People, citing unnamed sources, was first to report that the couple is "taking a break."

The Oscar-winning actors haven't been photographed together since April 22, the magazine noted, and Douglas has been relaxing on a yacht off the coast of Sardinia in recent days while his wife is at home in New York.

Douglas, 68, and Zeta-Jones, 43, have faced some struggles over the past few years, including his cancer diagnosis in 2010 and her battle with bipolar II disorder.

"The stress has taken a toll on their marriage," a friend told People.

The couple, who married in 2000 and have two children together -- Dylan, 13, and Carys, 10 -- reportedly decided to take some time apart after Douglas returned from the Cannes Film Festival in May.

People reports that neither of them has filed for divorce or moved for legal separation, and those close to the couple "are hoping they can work out their differences."