The couple were first linked in April 2011, with the Dolce & Gabbana model meeting King shortly after her split from boyfriend of two years Andy Brown.
The People reports that Gandy has confirmed the split, blaming their "busy schedules" for the end of their relationship.
"Sadly me and Mollie have split. It just wasn't the right timing and we were both so busy," he is quoted as telling the paper. "I have been over in the States three times this month and a relationship can't take that."
Speaking about his ex-girlfriend, he said: "Mollie is an incredibly beautiful, lovely girl and so grounded. But it just didn't work out. Maybe in a few years when we are at different stages in our career we can make it work."
The 31-year-old previously said that he envisaged the couple spending "the next 40 years together", following reports that he and King could move to India due to his plans to invest in property there.
Writing on Twitter, King has not commented on the split, but told followers that she is currently staying with her mother. She quipped: "Been staying at mums this week it's the best "hotel"!!! ...Although not sure what the reaction would be to late night room service!!!! (sic)"
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