Kate Winslet (L) (C Flanigan/Getty) and Saoirse Ronan (R) (Michael Loccisano/Getty).

Kate Winslet and Saoirse Ronan are set to play lesbian lovers in an upcoming romantic period drama, according to Deadline.

Winslet and Ronan are set to play the lovers in Ammonite, which will be directed by God’s Own Country’s Francis Lee.

The film tells the story of real-life palaeontologist and fossil collector Mary Anning, who was born in Dorset in 1799.

Deadline reports that the film will be set during the 1840s and will follow the unlikely romance between Anning and a London woman who she must unexpectedly care for.

Production on Ammonite is set to begin in March.

Kate Winslet and Saoirse Ronan: Gruelling roles

Oscar winner Kate Winslet has recently finished work on Avatar 2, work that proved to be gruelling. Director James Cameron recently said that the actress had to hold her breath underwater for seven minutes while filming.

Meanwhile, Saoirse Ronan, the Irish actress who has been nominated for three Academy Awards, recently said she was planning to take a break after finishing filming Mary Queen of Scots.

According to the Irish Independent, Ronan said she planned to take “most of the year off” after the gruelling role.

Ronan recently explained that she had to wear skirts she could not sit down in as well as corsets every day.

The film will be directed by Francis Lee, who directed critically acclaimed LGBT+ film God’s Own Country, which came out last year.

Francis Lee: God’s Own Country

The director tweeted today: “I’ll be taking a break from Twitter for a while as it looks like I’m making a film.

“Thank you everyone for your incredible support of God’s Own Country and me over the last 2 years. It’s time to make another one.

“See you soon,” he finished.

God’s Own Country was Lee’s feature directorial debut and starred Josh O’Connor and Alec Secăreanu.

The film tells the story of a young sheep farmer in Yorkshire whose life is changed when a migrant Romanian man begins working at the family farm.

The film went on to be a surprise hit across the world and was released to critical acclaim.

Saoirse Ronan previously made a name for herself in her native Ireland as an advocate for equal marriage.

The actress – who was 21 at the time – said she was excited and honoured that her first vote would be in Ireland’s historic marriage equality referendum in 2015.

She also said that, if the country voted against same-sex marriage, she would be “extremely disappointed.”