Although Scarlett Johansson and Sean Penn were photographed holding hands after the White House Correspondents Dinner on Saturday night, it turns out their PDA was a little less chaste inside the event. Fellow attendees were shocked to see ScarJo sitting in her older man's lap at the dinner table and engaging in a makeout session one source described to Us magazine as "intense."

"It happened right as the main course of the dinner was being put on the table," noted the onlooker. Tacky!

"She plopped down in his lap, and they were kissing," an observer told the New York Post, adding that they disappeared from the room for "an hour" and Sean returned with his tie mussed. Super-tacky!

After dinner, the pair was separated, but they reconnected at the after-party. "Around 1 a.m. Sean showed up and he and Scarlett were immediately side by side for the rest of the night," said an Us magazine source. "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."

Scarlett Johansson and Sean Penn have been photographed enjoying a short break together in Mexico.

Scarlett Johansson, the American actress who recently split from husband Ryan Reynolds has enjoyed a short getaway in Mexico with the actor Sean Penn, reports People Magazine.

The couple, who are rumoured to be dating, left on a private jet from Van Nuys airport on Tuesday morning (1st March 2011) and were photographed having dinner in Cabo San Lucas in Mexico later that night.

The pair then returned to Los Angeles on Wednesday where Johansson is finishing work on her highly-anticipated new movie 'We Bought a Zoo', with Matt Damon. It has been reported that 50-year-old Penn and 26-year-old Johansson enjoyed a dinner of lobster and margaritas during their brief stay in Mexico.

Earlier this week, they were spotted sharing a casual lunch at the popular Cuban restaurant 'Versailles' in Los Angeles.