Disney has taken its action-adventure "Mulan" off the August release calendar, ending hopes that Americans will return to movie theaters en masse this summer.

Last Thursday, the company said the film, which had most recently been set for release Aug. 21, was now "unset." No new release date was announced.

The move came three days after Warner Bros. said it would wait at least a few more weeks to release its expected blockbuster "Tenet" and hours after AMC, the world's largest chain of theaters, said it would postpone its planned reopening to mid-August, tying the new opening date to the release of "Mulan" and "Tenet." The "Mulan" delay could push the theater chain to wait until Labor Day weekend, when Paramount — for now — plans to release "A Quiet Place Part 2."

Originally scheduled for late March, "Mulan" was one of the first major pictures postponed because of the coronavirus pandemic and has served as a bellwether of the Hollywood uncertainty that followed in its wake. After several delays, the film had landed in late August, when the prospect of a summer release provided some reassurance that the industry would at least not lose two full seasons because of the virus.

But surges in California, Florida and Texas have made such a release increasingly impractical. Disney executives have also been watching the closing of theaters in Beijing due to outbreaks there; with Chinese stars and locations, "Mulan" is expected to generate much of its income in that country. China has begun to reopen theaters in the capital, but only in low-risk areas.

In contrast with rivals such as Universal, Disney stopped short last week of making wholesale changes that would have suggested it has given up on 2020 as a time of mass moviegoing. Although it pushed back movies in the top-tier "Avatar" and "Star Wars" franchises to 2021 and 2022, it kept Marvel's "Black Widow" and Pixar's "Soul," both scheduled for November, on the calendar.

And it did not give a 2021 date to "Mulan," leading experts to believe Disney would still like to release the movie in 2020.

The announcement had the kind of low-key quality reflective of how common uncertainty has become in American business during the coronavirus era. In contrast to the most recent "Mulan" delay a month ago, when studio Chairs Alan Horn and Alan Bergman gave a statement that the pandemic "has not changed our belief in the power of this film and its message of hope and perseverance," Disney announced the change last week as part of schedule moves for a variety of movies.

The company did not say it was moving "The New Mutants," a film in the X-Men series that could stay on the calendar for Aug. 28 and draw moviegoers in U.S. theaters that are open.