Olivier Sarkozy and Mary-Kate Olsen are planning to marry in June, a source reveals to Us Weekly. Credit: Shahar Azran/WireImage

Mary-Kate Olsen is taking longer than a New York minute to plan her wedding. Engaged since early 2014, the Elizabeth and James designer and her fiance, Olivier Sarkozy, will finally tie the knot next summer, a source reveals in the new issue of Us Weekly.

“They’re leaning toward a June event in the Hamptons,” says the source of the posh Long Island region about 90 miles from the couple’s $13.5 million New York City apartment. Olsen and Sarkozy, who proposed with a 4-carat vintage Cartier diamond ring — reportedly purchased for $81,250 at a Sotheby’s auction — have “changed their plans a million times,” adds a second insider. “Her family can’t even keep up!”

No matter the setting, friends and family are anxious to see the French banker, 46, and Ashley’s twin, 29, walk down the aisle. “Mary-Kate is funny and sweet,” says a source close to Sarkozy (who has kids Julien, 13, and Margo, 11, from his previous marriage to Charlotte Bernard). “Olivier’s friends understand what he sees in her.”

Olsen’s brood is also on board. "Mary-Kate's family thinks Olivier is the best thing to happen to her," an insider previously told Us of the former Full House star. "They love him."

As Us exclusively reported in March 2014, the actress, who will not be participating in Netflix’s Full House reboot, initially said no to her beau’s first proposal. “She wasn’t ready,” an insider told Us at the time. “She wanted to make sure he would be good to her.”

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