Los Angeles, Oct 16 (IANS): The standalone movie around the superhero character Flash has been pushed back to 2021, due to Ezra Millers involvement with the "Fantastic Beasts" franchise.

According to sources, Warner Bros. has pushed back the start of filming on the studio's still untitled standalone Flash film, reports variety.com.

The film never received a formal greenlight nor did it have a set release date, but it had been expected to begin shooting in March.

However, a script is still being tweaked and the studio officials think that it won't have enough time to get the script in shape in order for the film to make its original start date.

Miller, who will play the role of Flash, also has a key supporting role in "Fantastic Beasts" -- the "Harry Potter" spin-off series. The third film in the franchise begins shooting in July.

The standalone Flash film is now expected to commence production in late 2019. That means the superhero adventure won't release until some time in 2021.