Naomi Watts has said she is "absolutely terrified" about portraying Princess Diana in a new film based on the last two years of her life.

Naomi said: "She is a part of our history, an incredible woman and fascinating but a tragic ending.

"The filmmakers came to me and it's a good script and it's very scary and I kind of wanted to say no but I couldn't."

The British actress said she grew up watching Diana and said that taking on the new role will be "tough".

"There are a lot of people that knew her and a lot of books to read and so much information and one story is different to the next so it's hard to gauge what was the truth.

"It's going to be a tough one, it's a big beast to take on, I'll just try to do my best."

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