Kate Winslet and Saoirse Ronan will play lovers in a new movie.

Kate Winslet

Kate Winslet

The 'Titanic' star and the 'Mary Queen of Scots' actress have signed up to star in 'God's Own Country' writer-and-director Francis Lee's upcoming romantic drama 'Ammonite', Deadline reports.

The movie is set in an 1840s coastal town and follows the unlikely romance between palaeontologist Mary Anning and a wealthy London woman, to whom she unexpectedly becomes a nursemaid.

Production on the movie, which will be produced by Iain Canning, Emile Sherman, and Fodhla Cronin O'Reilly, is scheduled to begin in March.

Kate is currently filming 'Blackbird' and recently finished working on 'Avatar 2', while Saoirse can be seen on screen opposite Margot Robbie in 'Mary Queen of Scots'.

Saoirse's casting may have came as a surprise because she recently revealed she planned to take a long break after her challenging lead role in 'Mary Queen of Scots'.

She said: "I'm going to take most of the year off and travel, do a bit of writing and work with my friends on something small. We're all around the same age, which is unusual for me because I'd always been the young person working on my own."

The most challenging part of her role in the drama - based on Mary's real-life attempt to overthrow her cousin Queen Elizabeth I, resulting in years of imprisonment before facing execution - was wearing four skirts, as she couldn't sit down properly.

Asked about the costumes, she said: "Oh, corsets every day.

"We had, like, four skirts to wear at a time so you couldn't sit in a chair because you might crease the dress. We had to sit on these little swivel stools. You'd lift up your skirt and just drop it down over the stool so wouldn't even see it."