Britney Spears treated her boyfriend to a horseback-riding session to mark his 32nd birthday.

The Toxic hitmaker has been dating screenwriter/producer Charlie Ebersol for the last few months, and she organised a special treat for his birthday.

On Tuesday (30Dec14), Spears shared pictures of the couple at a stable, showing them both riding horses, and she added in a post on Twitter.com, "Birthday horses for my birthday boy."

The singer also uploaded a snap of Ebersol's towering birthday cake, which featured a clapperboard emblazoned with name and pictures from his life in the style of movie film, adding, "I believe it's clear that I won the birthday cake war!"

Ebersol previously designed a special pink cake for Spears' 33rd birthday on 2 December (14).