"They're taking time off for the time being, they've split," a source close to Leo told People. "It could just end up as a break but for now they're doing their own thing."
The on-again/off-again couple spent the weekend on separate coasts – Bar was in Los Angeles for the Young Hollywood Awards and Leo was spotted at New York City hotspot Avenue, where he was reportedly seen chatting with another woman.
"He was standing at the bar in front of everyone talking to a girl the entire night – and it wasn't Bar," one onlooker told People. "It was in no way behavior for a guy who has a serious girlfriend."
However, Leo and Bar were back together on Monday night, as the pair was photographed leaving a Barnes & Noble bookstore in Los Angeles.
A source close to the 23-year-old swimsuit supermodel said Bar's desire to get more serious with the actor could've caused the split.
"She wanted to move faster than he did, she wanted to move in together," the source told People. "So he broke it off."
Leo and Bar began dating in January 2006. The briefly split up in October 2007.
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