"The relationship had run its course. It's completely amicable, and they are remaining friends," the New York Daily News quoted a source close to the couple as telling Us magazine. The insider also revealed that Fox and Green "are both focusing on their careers."
Earlier this year, the actress had raised eyebrows when she attended the Golden Globes without her fiance. But Green, 35, later laughed off rumours of a split with Fox, 22, saying: "We usually go have dinner and have a glass of wine and laugh about it."
In a recent interview at a GQ bash, the actress played down any wedding plans, and said: "It's not going to be a big wedding. I'm not one of those girls. If it happens, it will be very low-key and quick and unplanned."
She also dismissed rumours that she and the former Beverly Hills 90210 actor might start a family together anytime soon. She said: "I feel like I need to set my career and do a movie other than Transformers. Then I'll explore family."