Getting cozy with Sarkozy!

All eyes have been on Mary-Kate Olsen and her beau Olivier Sarkozy since it was revealed late last month that the couple, who are 16 years apart in age, were dating.

Indeed, the fashion designer and former French president Nicolas Sarkozy's younger brother haven't exactly been under the radar. At the MoMA PS1 gala in NYC on Tuesday, witnesses tell New York Post's Page Six that Olsen, 26, and Olivier, 42, "couldn't keep their hands off each other."

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"The couple avoided photographers but then were seen smooching at the gala, which celebrated performance art," the paper adds.

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On June 14, the pair went for a stroll in NYC's West Village neighborhood with Olivier's underage daughter (with ex-wife and writer Charlotte Bernard). Olsen caused a stir when she lit up a cigarette.

Despite the odd coupling, Olsen -- who owns three successful fashion labels with her twin sister, Ashley -- is head over heels for him, a source recently told Us Weekly.

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"MK is constantly complaining about boys not being mature enough for her. She got the kids out of her system," the source explained. "Now being a businesswoman dominates her time, and she is rarely impressed with guys."

This article originally appeared on Mary-Kate Olsen, Olivier Sarkozy "Couldn't Keep Hands Off Each Other"