By Darren Waters
BBC News Online entertainment staff in Edinburgh
Dame Helen Mirren is to star as The Queen in a film about the aftermath of the death of Diana, Princess of Wales, director Stephen Frears has revealed.
The film is expected to go into production in May next year
"She will be great," said Frears, who said it would follow up his political TV drama The Deal about Tony Blair.
Michael Sheen, who starred as the prime minister, will reprise his role in the £5m film, which has been written by The Deal's screenwriter Peter Morgan.
With the working title The Queen, it is hoped it will get a cinema release.
Producer Christine Langan said: "No-one will be cast as Diana."
She said the film would focus on the events of the week of the princess' death and how they affected "The Queen, Britain and the people".
Michael Sheen (right) played Tony Blair in Channel 4's The Deal
"It looks at a moment in British history that was phenomenal," she said. "It is a snapshot of the country. It joins the dots of what went on that week."
The film is expected to go into production in May next year. No-one else has yet been cast.
Mirren is known for her roles in Prime Suspect and Calendar Girls, and played Queen Charlotte in The Madness of King George.
Channel 4's critically-acclaimed The Deal dramatised the events surrounding Tony Blair's rise to power as Labour leader and was also directed by Frears.
"We made The Deal just before the war with Iraq. Tony Blair's role as prime minister has been fascinating," Ms Langan said.
Frears, who also directed Dangerous Liaisons, High Fidelity and Dirty Pretty Things, revealed the casting at the Edinburgh International Television Festival on Sunday.
He was in conversation with the BBC director general Mark Thompson.