George R.R. Martin, the author of the mega-successful Game of Thrones books that have been turned into one of the biggest TV series in history, says a GoT movie is in the works.

In an interview after last week’s Emmy Awards, Martin revealed HBO series writers David Benioff and DB Weiss will be in charge as he will be too busy writing the final two books in the series to be involved.

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“There will be a movie but I will not be involved,” Martin said.

“I have too much to do. That is something HBO and the DB and David are dealing with.

“I have two more books to finish and I still have so much to do.

“The pressure is on. I am such a slow writer and the fans get upset that I don’t write faster.”

According to a production source the movie may go back in time, paving the way for some characters to return from the dead.

In perhaps the worst-kept secret in television, fans are now certain that character Jon Snow, played by 28-year-old actor Kit Harrington, will return to Game of Thrones in series six (due out in April next year).

Harrington has been spotted regularly in Belfast where the majority of the series is filmed.

Game of Thrones the show is due to finish at the end of season eight, with the next two seasons departing from the storyline of Martin’s books (though the author will be involved in the final two series).