'Guardians of the Galaxy Vol. 3' will start shooting in 2020.

James Gunn will return to helm the third edition of the Marvel Cinematic Universe franchise as soon as he's completed directing DC's 'Suicide Squad' follow-up, which is currently pulling together its cast.

According to The Hollywood Reporter, cameras will start rolling on 'Guardians of the Galaxy' film months before 'The Suicide Squad' film's August 2021 release date.

'Guardians of the Galaxy Vol. 3' was set to film this year, however, was delayed when Gunn was fired and then rehired by Disney following the unearthing of several controversial old Twitter posts in which Gunn made jokes about paedophilia, homosexuals and rape.

Marvel Studios President Kevin Feige previously said of filming: ''I won't say specifically [when Guardians 3 shooting will begin] but I will say we're delaying when the film would have originally been. But thankfully [Gunn] is back and he's doing it and all is right with the world.''

The upcoming film will see Chris Pratt return as lead hero Star-Lord as well as Drax (Dave Bautista), Mantis (Pom Klementieff) and Groot (voiced by Vin Diesel).

Feige, 45, isn't the only person who's pleased about the director's return as Zoe Saldana - who plays Gamora in the sci-fi series - previously admitted she was ''very proud'' of Disney executives for bringing Gunn back.

She said: ''I was very proud of Disney and all of the executives there. They're sending a very strong message that, yes, accountability is important. It is a must.

''We're not going to surrender that moving forward. But when the opportunity presents itself where it's just the first step, redemption must be the second step.''