Britney Spears Engaged to Her Former Agent Jason Trawick (Report)

Kevin Mazur/WireImage via ABC

The pop star's beau has popped the question Thursday night on his 40th birthday.

Britney Spears is getting married.

The pop star's boyfriend and former agent, Jason Trawick, proposed on his 40th birthday Thursday night in Los Angeles with a Neil Lane diamond ring, People magazine reports. "He surprised her after she gave him his gifts and after they had cake last night," a source is quoted as saying. They're reportedly celebrating the engagement Friday night in Las Vegas.

"OMG. Last night Jason surprised me with the one gift I've been waiting for. Can't wait to show you! SO SO SO excited!!!! Xxo," Spears said in a coy tweet on Friday.

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Spears, who recently celebrated her 30th birthday, went official with Trawick, an agent at William Morris Endeavor Entertainment who used to represent her, in May 2010. They decided, amicably, to end their professional relationship to focus on their romantic one.

This will be Spears' second, seemingly less "Toxic" trip down the aisle. The singer and mother of two sons, 6-year-old Preston and 5-year-old Jayden, divorced their father, Kevin Federline (aka K-Fed, a former back-up dancer and would-be rapper) in 2007, beginning a downward spiral that appeared to be reversed under the court-ordered conservatorship of her father, Jamie Spears, and a low-key relationship with Trawick.

Representatives for Spears did not respond to comment. Trawick could not immediately be reached.