Hollywood maverick Quentin Tarantino has cast doubt on plans to make an R-rated "Star Trek" movie and says he is "steering away" from it.

Tarantino has been linked to a new instalment in the long-running sci-fi film franchise for months, after reportedly making a successful pitch for an edgier story to studio officials at Paramount Pictures, reports aceshowbiz.com.

Previous reports suggested a screenplay is in development, but Tarantino now says he is moving away from the "Star Trek" project, for which he never entered an official deal.

"I think I'm steering away from 'Star Trek', but I haven't had an official conversation with those guys (studio bosses) yet," he told portal Consequence of Sound.

The last "Star Trek" movie, "Star Trek Beyond", was released in 2016, and featured Chris Pine as Captain Kirk and Zachary Quinto as Spock.

Tarantino says he almost chose to hold back his latest release "Once Upon a Time in Hollywood" and make it his swansong after previously vowing to step away from filmmaking after completing his 10th movie.

"In a strange way, it seems like this movie, 'Hollywood', would be my last," he said of his ninth film. "So, I've kind of taken the pressure off myself to make that last big voila kind of statement. I mean, to such a degree there was a moment when I was writing (it) and went, 'Should I do this now? Should I do something else? Is this the 10th one?' "

Tarantino decided not to delay the project unnecessarily, and although he still plans to bow out after movie number 10, he doesn't think his final film will be another big production, like "Once Upon a Time in Hollywood" was.