Kelly Macdonald has replaced Reese Witherspoon as the lead voice in Pixar’s “Brave.”

Witherspoon was attached to portray princess Meria in Disney’s animated pic but was forced to exit the project due to scheduling issues.

Formerly known as “Bear and the Bow,” “Brave” tells the story of an impulsive princess (Macdonald) who aims to shed her royal ties and become the world’s first great female archer.

The project is Pixar’s first-ever female-driven feature. Emma Thompson, Craig Ferguson and Billy Connolly also lend their voices to the CGI-animated film.

The Macdonald casting marks the second major substitution on “Brave.” Brenda Chapman, who co-helmed DreamWorks’ “The Prince of Egypt” and penned the script for “Brave,” was originally onboard to direct the CGI fairy tale but was forced to ankle the project last fall. Mark Andrews has since come on as director. Andrews was the story supervisor on “The Incredibles.”

“Brave” is one of two Pixar pics skedded for 2012. The company will release a sequel to “Monsters, Inc” on Nov. 16, 2012.

Macdonald, who stars in HBO’s “Boardwalk Empire,” can next be seen in “Harry Potter and the Deathly Hallows: Part 2.”

She is repped by ICM.