The actress, who starred as Lady Rose MacClare on the PBS drama, confirmed to PEOPLE that she will not appear in the Downton Abbey movie, which has officially been greenlit.
“I’m sadly not, but I’m so excited for it — I’m going to be front row,” James, 29, tells PEOPLE of not being part of the film.
“I spoke to Laura [Carmichael] not long ago and was texting Michelle [Dockery] about Love Island and it’s going to be really exciting. And the whole gang is coming back,” shares James, who stars in Mamma Mia! Here We Go Again, in theaters Friday.
As for why James’ character will not be featured in the film, the British star confirms that “it wasn’t schedules.”
She explains: “My character Rose moved off to New York, so it would be farfetched to bring her back.”
“I would have loved to have come back for a scene, but for a movie it can’t be like a Christmas special and it needs to be a focused storyline,” James adds, noting, “There was no space for Rose.”
James might surprise Downton Abbey fans in Mamma Mia! Here We Go Again, which finds the actress portraying a young Donna (Meryl Streep’s character) and singing along with her group The Dynamos.
The sequel to the much-beloved film 2008 film, which is based around the music of ABBA, takes place back on the Greek island of Kalokairi five years later with Amanda Seyfried’s character running her mother Donna’s inn — with the help of her mom’s former bandmates, Tanya and Rosie (Christine Baranski and Julie Walters).
The entire original cast reunited for the film, including Colin Firth and Pierce Brosnan, with James and Cher as the newcomers. Cher plays Donna’s mother, Ruby Sheridan.
Downton Abbey, which ran for six seasons, followed the lives of the elite Crawley family and the servants who worked in their country home. The period piece took place in the 20th century.
Last week, it was announced that the series would be returning as a film, with production scheduled to start this summer.
“Since the series ended, fans of Downton have long been waiting for the Crawley family’s next chapter,” commented Focus Features chairman Peter Kujawski. “We’re thrilled to join this incredible group of filmmakers, actors and craftspeople, led by Julian Fellowes and Gareth Neame, in bringing back the world of Downton to the big screen.”
RELATED VIDEO: You’re Going to Love Watching the Cast of ‘Downton Abbey’ Give Their Best Emoji Faces!
While plot details are still unknown, Brian Percival, who directed the original series’ pilot, will direct the film.