Suki Waterhouse joined her boyfriend Bradley Cooper at the American Hustle premiere in New York City on Sunday, marking their first public appearance as a couple.

Suki Waterhouse Attends 'American Hustle' Premiere

While Waterhouse, who models for Burberry, didn’t walk the red carpet with Cooper, she did appear at his side during the after party at Cipriani. Matching her actor beau’s dark gray suit, Waterhouse, 21, wore a thin gray turtleneck as they snacked on chocolate covered strawberries. The couple of nine months shared a table with Cooper’s American Hustle costars.

"Guests were greeted with cocktails before entering the massive space, which was decked out '70s style complete with sparkling disco balls," a source told Us Weekly. "Cooper posed with fans for photos, and later caught up over dinner [with Waterhouse.]"

Waterhouse Won't Talk About Bradley Cooper

Waterhouse remained relatively tight-lipped about the Silver Lining’s Playbook actor in an interview for the January issue of Elle UK, spending a few sentences explaining why she doesn’t want to open up about their relationship.

"I don't talk about my boyfriend because it's boring. At least, that's what I decided to tell you when you asked," she said. "I do think whatever I say will sound weird. But the truth is, if I start talking about him, I probably won't be able to stop. And I don't really want to talk about him, you know?"

Waterhouse and Cooper, 38, were first spotted together back in March while Cooper was filming American Hustle in Boston after meeting on Feb. 21 at the Elle Style Awards.

Cooper previously dated his The Words costar Zoe Saldana until December 2012. Saldana secretly married artist Marco Perego, a longtime friend, in June of this year.

– Chelsea Regan

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