Miley Cyrus and Liam Hemsworth are "definitely over," according to a new report. The young engaged couple have reportedly been sleeping in separate rooms after Liam pulled the plug on their relationship.

According to multiple sources of Us Weekly, Liam, 23, was the one who called it quits with 20-year-old Miley.

"They are definitely over," an insider told the magazine.

It's not clear what broke them apart, but there are reports of jealousy and third-parties floating around for some time now.

Breakup rumours about the two aren't new. Ever since they got engaged in June last year, with "The Hunger Games" actor proposing to the former Disney star with a 3.5-carat diamond ring, they are besieged with constant split reports.

Just last month, Miley was said to be furious after learning that her fiancé was communicating with "Mad Men" actress January Jones, 35. Liam and January were reportedly caught getting hot and heavy with each other, according to Star magazine.

Meanwhile, Miley and tween heartthrob Justin Bieber are allegedly getting close, perhaps too close for Selena Gomez's comfort. Selena, Justin's on-off girlfriend, apparently told him to stay away from Miley.

"Justin and Miley hooked up a few years ago," a source told Life & Style. "Then he started dating Selena. It created this whole jealousy thing between them. Now Selena doesn't want Justin anywhere near Miley - and they've been fighting about it!"