Scarlett Johansson, Sean Penn Make Out at White House Dinner

USMagazine, Monday, May 2, 2011, 6:11am (PDT)

The PDA parade continues!

Despite being in the presence of President Barack Obama and celebrities like Mila Kunis and Donald Trump, an eyewitness tells Us Weekly that Scarlett Johansson was engrossed in an "intense" makeout session with Sean Penn at Saturday's White House Correspondents Dinner in Washington, D.C.

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"It happened right as the main course of the dinner was being put on the table," the witness says, adding that Johansson, 26, sat in Penn's lap during part of the meal.

The touchy-feely moments didn't end there. Later in the evening, the handsy twosome ventured into one of the courtyard areas with a group of pals including Michelle Trachtenberg.

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"Scarlett was pawing at Sean, holding on to his hip while he was smoking. She gave him a short kiss," the witness says. "But then they took a walk some 30 feet away, broke off from the group and kissed some more."

The two later separated, only to be reunited at the Vanity Fair afterparty.

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"Around 1 a.m. Sean showed up and he and Scarlett were immediately side by side for the rest of the night," an insider recounts. "When they were walking out the door, Sean stopped her, took off his jacket and put it on her shoulders, saying, 'It's cold out there.' They then grabbed hands and walked out before 3 a.m."

What brought Johansson to the nation's capitol in the first place? "I really want to get more involved," she told Us.

As for Penn, 50? "Well, the dinner, but I also have a lot of meetings on The Hill this week," he told Us. "I'm mostly here for Haiti, and I want to help bring some attention to that crisis."

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