The late Princess Diana has been described as a "powerful sympathetic person" by screenwriter Ryan Murphy.

Princess Diana

Princess Diana

The 51-year-old creative mastermind is working on a new instalment of the American television series 'Feud', which will be based around Prince Charles and Diana - who tragically passed away in 1997 aged 36 years old - and their relationship, including their divorce in 1996.

But the American director and producer has hinted he feels there is a slight pressure on him because he has to cast the lead role of Diana "in a really cool way".

Speaking to WWD about the project, he said: "[Diana] is obviously a powerful, sympathetic person and we have to handle her in a really cool way. "

And he is desperate to "get it in the ballpark" when he signs an actor up for his roles and will do all he can during the editing process to make sure the outcome is exactly how he intended it to be.

He added: "Whenever I cast somebody [to play another famous person], I want to get it in the ballpark. Then you just shoot the s**t out of the make-up testing and get it right."

However, Murphy has yet to secure any actors for the production yet.

The filmmaker - who created the popular series 'Glee' - has revealed he intends to portray the "outspoken" character of Diana - who has sons Prince William, 34, and Prince Harry, 32, with the Prince of Wales - because he "liked" that side to her personality.

He explained: "She stood for a lot and I like how she was so outspoken and that's what her story is going to be."