George Clooney and Stacy Keibler have been the subject of split rumors for weeks, but the couple silenced naysayers when they arrived at the Argo premiere in Beverly Hills October 4.

The film's producer, 51, and the Supermarket Superstars host, 32, wore matching black ensembles as they walked down the red carpet. Keibler turned heads in a vintage Alaia dress, Giuseppe Zanotti shoes and Neil Lane jewelry, while Clooney wore a classic black suit.

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According to an onlooker, Clooney kept "his hand on the small of her back" as Keibler placed "her arm wrapped around his back" while posing for photographers. "They had big grins on their faces and made sure to exchange hellos with Ben Affleck [the film's star, producer and director]."

Though the couple did not speak to the press, they did mingle with several other stars on the red carpet. "Geroge even held Stacy's hand as he bent down to squeeze [Aidan Sussman,] the kid who plays Ben's son in the movie," the onlooker tells Us Weekly.

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Clooney and Keibler went public with their romance in September 2011 at the Toronto Film Festival. They spent the summer of 2012 together at Clooney's estate in Lake Como, Italy. (Keibler's married pals Channing Tatum, 32, and Jenna Dewan, 31, even paid them a visit in July!)

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In mid-September, Clooney's rep issued a statement denying a British tabloid's report that he and Keibler had called it quits. "A story published by a London tabloid, The Sun, concerning George Clooney and Stacy Keibler [is] not true," the rep told Us.

This article originally appeared on George Clooney, Stacy Keibler Resurface at Argo Premiere Amid Split Rumors