Emma Watts has resigned as chief of 20th Century Studios less than a year after the Disney merger closed in March 2019.

Her existing team remains in place at 20th Century and a successor is expected to be named in the coming weeks.

Watts, who had served as vice chairman and longtime president of production at 20th Century Fox before the studio was absorbed into the Disney empire, was one of the few top Fox execs to survive the union alongside Searchlight co-chiefs Nancy Utley and Steve Gilula. (Fox 2000 president Elizabeth Gabler, who was initially set to join Disney, was cut from the team as the merger closed.)

Watts — whose credits include the Avatar and X-Men franchises — has yet to announce her next move.

It's no secret that the transition has been difficult for the executive, who previously had dominion over the slate of a major Hollywood studio. Now, 20th Century may make as few as four movies for the big screen annually; there's also an increased focus on making content for Disney+ and Hulu. And Marvel pics, such as Deadpool, are now handled by fellow Disney silo Marvel Studios.

"I am writing to you today to share that, after much reflection, I’ve made the difficult decision to step away from Twentieth Century," Watts said in a note sent to staff Thursday morning. (Disney said earlier this year it was dropping "Fox" from the 20th Century and Fox Searchlight labels.)

"Over the past many months, it has been my top priority to continue to foster great filmmaking while leading this team successfully through the integration period with Disney. After reaching this point, I approached [Walt Disney Studios co-chairmen] Alan [Horn] and Alan [Bergman], realizing that it was now time for me to pursue new opportunities," she continued.

Added Horn and Bergman in a separate statement: "Emma has made many wonderful contributions to Fox over the past two decades, shepherding a number of memorable films to the screen. We truly appreciate and thank her for her commitment and partnership in overseeing the transition in this past year and wish her the best."

Watts is coming off a tough 2019 at the box office, with the exception of James Mangold's Oscar contender Ford v Ferrari, and the upcoming releases Call of the Wild and New Mutants may underperform. Fox had one of its worst years in history in terms of domestic revenue.

Watts has strong ties to filmmakers, producers and talent, including Mangold and Avatar director James Cameron. She also worked for years for Jim Gianopulos, who now runs Paramount. As of now, there are no official talks between Watts and Paramount. Watts also worked at Fox for Tom Rothman, chief of Sony Pictures.

"It’s hard to imagine Fox without Emma," Cameron said in a statement. "Her creative input and support were invaluable on Avatar, and even more so on the sequels. She deeply understands movies in her DNA — how they work, what’s wrong when it’s not working, how to fix it. I’ve always felt a strong creative synchronicity with Emma, and give her input a great deal of weight. It’s been great to have such a strong, knowledgeable, and committed person as my studio head. And I would add to that list — friend. I can’t wait to see what she does next, because I have no doubt it will be big."

Actor and producer Ryan Reynolds, whose upcoming summer comedy Free Guy is from 20th Century, also weighed in. "Deadpool would never have happened without Emma Watts. And certainly wouldn’t have been as good. I hope to continue working with her wherever she decides to go," he tweeted.

Steven Spielberg, who is directing the Christmas 2020 musical West Side Story for 20th Century, likewise praised the executive. “Emma is a studio executive in title, but a filmmaker at heart," he said in a statement. "Her support and willingness to take risks is what this business has always thrived on. I can’t wait to see what Emma does next and I’ll work with her again on anything at any time."

Watts' memo to staff is below. 

Team,

I am writing to you today to share that, after much reflection, I’ve made the difficult decision to step away from Twentieth Century.

Over the past many months, it has been my top priority to continue to foster great filmmaking while leading this team successfully through the integration period with Disney. After reaching this point, I approached Alan and Alan, realizing that it was now time for me to pursue new opportunities.

I started at Fox 22 years ago — Titanic was in theaters, George Lucas had just announced his second Star Wars trilogy, and X-Men was in development. I was a young creative executive eager to learn the business, and from day one I was welcomed. Who knew that together we would add Night at the Museum, Bohemian Rhapsody, The Martian, Deadpool, Logan, Steven Spielberg's upcoming West Side Story and, of course, Jim Cameron’s Avatar to the studio’s already storied legacy. It was a front-row seat to an incredible evolution culminating in Fox becoming a part of one of the greatest media companies that continues to shape our industry on a global scale. 

Disney has an immensely gifted and creative leadership team, and I am so thankful to have had the opportunity to be a part of the expanded company. Even more so, I am deeply grateful for the time I’ve spent with all of you. Thank you for your dedication to supporting great talent and storytelling, and above all, for your friendship. 

I’ll be here and available for the next few weeks to support the transition process. 

All the best,

Emma 

Jan. 30, 12:38 p.m. Updated with statement from James Cameron.