The news comes after the pair signed an exclusive deal with Netflix.
"There are only so many hours in the day, we could not do justice to both Star Wars and our Netflix projects," a statement given to Deadline read.
They added that "getting to talk about Star Wars" with creator George Lucas had been "the thrill of a lifetime".
They said: "We love Star Wars. When George Lucas built it, he built us too."
Lucasfilm president Kathleen Kennedy said that they would be welcomed back in the future. "David Benioff and Dan Weiss are incredible storytellers," she said.
"We hope to include them in the journey forward when they are able to step away from their busy schedule to focus on Star Wars."
According to a Disney release schedule published in May, the trilogy is due to be the next set of Star Wars films, following this December's The Rise of Skywalker, the final chapter of the Skywalker family chronicles.
The next films are scheduled for 2022, 2024 and 2026, and are set to usher in a new era for the famous franchise.
There was much fanfare when the two writers were unveiled as the writers behind the new Star Wars movies last February.