» Sign Up For Breaking News Alerts» Like Us On Facebook

The couple have been married for six years.

Moore, 49, issued a statement saying she was making the announcement "with great sadness and a heavy heart."

"As a woman, a mother and a wife there are certain values and vows that I hold sacred, and it is in this spirit that I have chosen to move forward with my life," Moore said. "This is a trying time for me and my family, and so I would ask for the same compassion and privacy that you would give to anyone going through a similar situation.

Kutcher, 33, confirmed the split on his Twitter page, writing, "I will forever cherish the time I spent with Demi."

"Marriage is one of the most difficult things in the world and unfortunately sometimes they fail. Love and Light, AK," he wrote.

The couple were married on Sept. 24, 2005.

Rumors of trouble in the marriage have persisted in recent weeks, fueled by reports that Kutcher had a fling with another woman during a trip with friends to San Diego.

Sara Leal of San Diego claimed that she had unprotected sex with Kutcher after meeting the star at the Hard Rock Hotel

In an interview with US Weekly magazine, San Diegan Sara Leal claimed she had sex with Kutcher after a night of partying at the Hard Rock Hotel in downtown San Diego on Sept. 24.

According to Leal, she and Kutcher, 33, had unprotected sex, and the actor told her he was separated from the 49-year-old Moore, his wife of six years.

The marriage was the first for Kutcher, and the third for Moore, who had three children with her previous husband, actor Bruce Willis.

Earlier this year, Kutcher and Moore began the Demi and Ashton Foundation aimed at ending child sex-slavery.