Anna Faris quits Mom just days before season 8 begins filming

Next series was due to begin shooting on 14 September

Anna Faris and Allison Janney in 'Mom' (CBS)

Anna Faris has quit the CBS sitcom Mom ahead of its forthcoming eighth season.

“The past seven years on Mom have been some of the most fulfilling and rewarding of my career,” the actor said in a statement.

“I’m so thankful to [creator] Chuck [Lorre], the writers, and my amazing castmates for creating a truly wonderful work experience.

"While my journey as Christy has come to an end, allowing me to pursue new opportunities, I’ll be watching next season and rooting for my TV family.”

Faris’s departure comes just days ahead of the show beginning production on its eighth series, with the shoot scheduled to begin on 14 September.

Mom, which has been nominated for 10 Emmy awards, starred Faris and Allison Janney as Christy and Bonnie, a dysfunctional, alcoholic daughter and mother who, after being estranged for years, try to rebuild their lives and stay sober. Janney has not responded to the news on social media.

It is currently unclear exactly how Christy will be written out of the show, but her exit is expected to be addressed in the first episode of season eight. The series also stars Mimi Kennedy, Jaime Pressly and Beth Hall.