is in early negotiations to take on the lead female role, opposite
, in Clint Eastwood's upcoming movie, reported Contactmusic.
Jaimie Alexander, 30, and Evangeline Lilly, 34, were previously linked to the part, as was Kate Mara, 31, before she was snapped up for Fantastic Four.
Meanwhile, Cooper, 39, will star as Navy Seal Chris Kyle in the film, which will follow the story of the expert marksman, who was killed by a discharged war veteran suffering from post-traumatic stress.
The film will be adapted from Kyle's book, American Sniper: The Autobiography Of The Most Lethal Sniper In US Military History.
It is not yet known who Miller will play, but is is believed she's landed the role of Kyle's wife, who is left to handle their family home while her husband is away.
Shooting for American Sniper is set to kick off in April.