11/08/2006 at 07:25 PM EST
In what may signal a custody battle to come, Kevin Federline filed a response Wednesday to wife Britney Spears's divorce claim in L.A. Superior Court.
In the surprisingly quick reply, Federline, like Spears, has made a claim for sole custody of their kids, Sean Preston, 1, and Jayden James (born Sept. 12), with visitation rights for Spears.
"It's not that unusual, but if you want to send a message that you want to be amicable, (both parties) would seek joint custody," says Lynn Soodik, an L.A. family law specialist.
"That he's seeking sole custody leads me to believe they're heading to a costly battle over the kids," she adds.
Federline also asks for spousal support.
According to a statement from his lawyer, Mark Vincent Kaplan: "Kevin is prepared to go the distance in order to do what he feels is necessary to protect and safeguard the children and will not be intimidated or dissuaded from pursuit of those goals."
In coming days, Federline and his lawyer will have to decide whether to contest the couple's prenuptial agreement, as well as negotiate a temporary support and custody arraignment.
Reps for both sides had no comment.