Pop singer Britney Spears [ tickets ] has filed for a divorce from Kevin Federline, her husband of just over two years.

Spears, in a filing dated Monday (11/6) in Los Angles County Superior Court, cited "irreconcilable differences" for the split, and is seeking custody of the couple's two children, Sean Preston, 1, and two-month-old Jayden James.

Legal documents filed by Spears apparently were first posted online today (11/7) on the gossip site TMZ.com. The couple reportedly signed a prenuptial agreement.

Federline is a dancer and aspiring rapper who issued his debut album last week.

On Monday night, Spears made a brief, surprise appearance on CBS-TV's "The Late Show with David Letterman."

"I'm just such a huge fan," Spears told Letterman. "I had to stop by."

"That's very nice of you to say," Letterman responded.

"I wasn't talking about you," Spears said. "I was talking about Will Ferrell. Do you know where he is?"