People fully vaccinated against COVID-19 can return to movie theaters mask-free at three of the United States' largest cinema chains in new guidelines updated Friday.

AMC Entertainment, Cinemark and Regal Cinemas said on their websites that moviegoers who are not fully vaccinated will be asked to continue wearing masks and that other social-distancing measures and cleaning protocols will remain in place.

"In accordance with CDC guidelines, masks are not required for guests who are fully vaccinated," AMC said on its website, referring to the U.S. Centers for Disease Control and Prevention. "If you are not fully vaccinated, we ask that you continue to wear a mask throughout the theater unless actively enjoying food or drinks."

Similar updates to mask policy were made on Regal and Cinemark websites. All three chains said they would follow state and local mandates on mask-wearing, which may be different from the CDC guidelines.

The changes for movie theaters come two weeks after the CDC said that fully vaccinated people need not wear masks in any setting.

Moviegoing has begun ramping up in the United States and the U.K. after lengthy pandemic-related closures and a lack of new film releases.

Movie studios and theater chains last week launched a Schwarzenegger-promoted "Big Screen is Back" campaign, previewing a summer filled with blockbusters including the new "Fast & Furious" movie and the superhero film "Black Widow."

Hollywood studios are closely watching box office receipts for two major films being released this weekend – "Cruella," a prequel story about the villain in "101 Dalmatians," and the thriller "A Quiet Place Part II."