Renee Zellweger and Bradley Cooper. (WENN.COM)

Renee Zellweger's romance with Bradley Cooper is stepping up a gear. The pair has been spotted house-hunting together in Los Angeles.

The Hollywood couple has been dating since summer 2009 and the pair soon proved they were serious after The Hangover star introduced his Oscar-winning lover to his parents in September.

And despite rumours suggesting Cooper was keen to re-locate to New York, where Zellweger lives, it seems the Bridget Jones star is happy to settle in L.A. with her beau.

A source tells New York Post gossip column PageSix, "Until Renee, Bradley had a reputation as a ladies' man and a heartbreaker, but he seems so happy with her. They prefer to stay in rather than hang out at showbusiness parties, and he has already introduced her to his parents."

Cooper has previously dated Jennifer Aniston and Cameron Diaz, while Zellweger was briefly married to country singer Kenny Chesney.