Seydoux played Dr Madeleine Swann in Spectre, the most recent Bond film, which was released in 2015.
Bond 25 was originally scheduled to be released on 8 November before moving to 14 February 2020.
Daniel Craig will officially star as Bond, although it’s expected to be his very last outing as the spy.
The story sees Bond start a relationship with Tylyn Mignonne, a film star whose husband is connected to The Union, a recurring crime organisation within the 007 novel series.