According to reports, Agron, who stars as Quinn Fabray on the Fox hit series Glee, moved out of the home the two shared last week.
Considering that Agron, 24, and Pettyfer, 20, never officially confirmed they were together – they dodged engagement rumors while promoting their movie – reports of why they may have split are sketchy.
According to some reports, Agron initiated the split shortly after pictures – shot by famed Lindsay Lohan photographer Tyler Shields – were released of a barely clothed Pettyfer with models Lydia Hearst and Leven Rambin.
But the shoot reportedly took place long before the duo even began dating.
Agron was first spotted with the British actor last August while filming the action flick together. He made a pit-stop on the Glee set, further winning over Agron – and her costars.
Although the two played coy, one source who had spotted the couple out and about told PEOPLE, "Alex was making Dianna laugh so much that her face was beet red."
Reps for Pettyfer and Agron haven't returned a request for comment.