He recently teamed up with the series' star Matt Damon to put together plans for a fourth film, but the project was reportedly thrown into chaos when Greengrass quit, amid whispers of a disagreement over the script.
Greengrass has now spoken out to dispel rumors of a falling-out with bosses at Universal, and allay fears that the project has been put on ice.
He says in a statement, "You won't find a more devoted supporter of the Bourne franchise than me. I will always be grateful to have been the caretaker to Jason Bourne over the course of The Bourne Supremacy and The Bourne Ultimatum. I'm very proud of those films.
"My decision to not return a third time as director is simply about feeling the call for a different challenge. There's been no disagreement with Universal Pictures. The opportunity to work with the Bourne family again is a difficult thing to pass up, but we have discussed this together and they have been incredibly understanding and supportive.
"Jason Bourne existed before me and will continue, and I hope to remain involved in some capacity as the series moves on."
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