This pair left on a private jet from Van Nuys airport Tuesday morning, then were spotted having dinner in Cabo San Lucas, Mexico, that night, according to sources.
Early Wednesday morning, they returned to Los Angeles where Johansson is shooting the film We Bought a Zoo with Matt Damon.
On the menu during their Mexican meal? Penn, 50 and Johansson, 26, reportedly enjoyed lobster and, of course, margaritas.
Earlier this week, the twosome were seen sharing a casual lunch at the popular Los Angeles Cuban restaurant, Versailles, where Johansson had her leg draped over Penn.
On Feb. 5, the couple raised eyebrows when they stayed unusually close to each other at a party celebrating Black Swan at the L.A. hotspot Sunset Tower Hotel, then reportedly left together. "They were flirting with each other all night, pretty much ignoring everyone else," a source told PEOPLE at the time.
Scarlet's represntive told PEOPLE at the time that they the two were not dating.
Neither of their reps have commented on the pair's most recent sightings.
Johansson and Ryan Reynolds, 34, split in December after two years of marriage. In August of 2009, Robin Wright, 44, filed for divorce from Penn. The couple had been married 13 years.
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