Scarlett Johansson and Sean Penn arrived at Reese Witherspoon's Ojai wedding on Saturday, according to People magazine.
"Scarlett is Jim's client, but no one, including the bride, knew she would have turned up with Sean Penn," CBS news reports a source as saying. "Turning up at a wedding with your boyfriend is definitely a huge statement, especially that wedding. What it's doing is announcing to the whole of Hollywood that they are serious."
Johansson, 26, and Penn, 50, have not commented on the reports but Johansson's spokesperson denied the two were dating in early February.
"Scarlett and Sean are not dating, they have been friends for years," Johansson's representation told E! Online. "Nothing more, nothing less. They have been talking over the last few months regarding Haiti Relief and Scarlett's upcoming trip to Haiti as Oxfam's Global Ambassador."
Ryan Reynolds, Johansson's husband of two years, filed for divorce in December. The two were wed on Sept. 27, 2008 in Canada after dating for about a year. They have no children. Reynolds cited irreconcilable differences as the reason for the split, according to the legal papers.
Wright first filed for divorce in December 2007 but later withdrew her petition in April 2008. She was back in court in April 2009 asking for legal separation, but the couple reconciled a month later. The actress sought divorce a second time last August citing irreconcilable differences. The two officially divorced on July 22.
It was the second marriage for Penn, 49, and Wright, 44. The couple has two children together, 19 year-old daughter Dylan, and 17 year-old son Hopper Jack. The divorce was finalized in Marin County, California.
Johansson is currently shooting "We Bought A Zoo" with Matt Damon in Los Angeles and is set to reprise her "Iron Man 2" role as the Black Widow and her alter-ego Natasha Romanoff in the spinoff film "The Avengers," set for release on May 4, 2012.
Johansson and Penn's reps had no immediate comment on the most recent reports.