The child support battle between Britney Spears and her ex, Kevin Federline, is escalating.

According to Us Weekly, a source told the publication that Federline "flatly rejected" Spears' team's child support payment proposal after the former backup dancer requested an increase in monthly payments back in February.

The tabloid reports that Federline is now seeking to take the pop star to court.

"Kevin truly wanted to try and settle the child support payment increase without getting the courts involved out of respect for Britney, and of course, their two sons," the source claimed, adding that Federline is now asking for "a once yearly income and expense declaration from Britney including most recent tax returns filed" in order to determine a new payment amount.

Back in February, it was reported that Federline, who is currently paid $20,000 a month in child support payments from Spears, was seeking an increase in child support payments following the success of Spears' Piece of Me Las Vegas residency, which earned $137 million across four years.

Spears and Federline share two sons together: Jayden, 11, and Preston, 12.

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