Naomi Watts shared that she strangely felt Diana's presence while filming for the biopic "Diana". The feeling, Naomi said, was like Diana giving her permission from her grave for her to play her life. The experience gave her the much needed confidence to embrace the character, Naomi said.

Naomi talked about her hesitation on being fit for the role in an exclusive interview to Mail Online.

"So I found myself constantly asking for her permission to carry on. I had saturated myself with Diana and her life and I felt this enormous responsibility of playing this iconic woman. It felt like I was spending a lot of time with her. There was one particular moment when I felt her permission was granted. That won't sound right in print, I know. There was a lot of hesitation on my part before I agreed to do it. Obviously I was taking on one of the most famous women of my time and an awful lot of pressure comes with that."

"You want to get it right, and everybody is going to have an opinion on the film and how she should be portrayed. It's very daunting. But then I also knew that the exciting roles, the best roles, come with a risk. In the end I decided that I couldn't not do it. This was a story that had to be told - it's an important story - but it was definitely the hardest thing I've ever done. It's as close as I ever want to get to a character."

"I lived in a house in Kensington and at 5.30 in the morning on my first day there, in my jet-lagged state, I went for a run not really knowing where I was going. All of a sudden I looked up and I was at the gates of Kensington Palace - that felt very eerie. I think I became a little obsessed. I felt very connected to her. I was very relieved to finish and leave her behind. But now that the film is ready to come out all of those feelings have come back to me again."

Naomi also shared that one of the reasons why she was hesitant at first to play the role of Diana was that her looks were in no way similar to Diana.

"I'm sure if someone placed an ad and said, "We're looking for the best Diana lookalike," there would be about 7,000 other women before me. But I soon realised it's not just about matching her physically, it's about getting inside her - getting the interpretation right."

To overcome this, Naomi said that she was more than willing to spend an hour be applied prosthetics each day of shooting for Diana. She had prosthetics on her nose and had to hide her hair under different wigs.

She also said that she took in her heart to study Diana's nuance like how she moves her head, how she smiled.

"She had a very expressive face,' she says. 'And she had that sideways smile we all remember, and those big eyes and a strong, athletic walk."

Naomi recalled that she was deeply affected when she first heard about Diana's death.

"I was in Canada filming what ended up being a bad TV movie with Rob Lowe. I was at dinner with him and his wife when the news spread around the restaurant that she had been in a crash.By the time we got back to the hotel, Diana had died."

"I remember being quite traumatised by it. I grew up in England and like everyone watched the Royal wedding. And later when I was in Australia or working in America she was still very present in all of our lives, on the television and in the newspapers. It was all so shocking."

She said that now, she was more than thankful that because of her role in the biopic, she was able to get to know Diana more intimately through her friends she gets to talked with.

"It was very useful meeting her old friends as it meant I could pick up little details, little stories and make sure I was doing it right. The people I met who knew her were unanimous in their praise of her extraordinary sense of humour and her cheekiness."

'They also all said she had quite a rebellious streak, which I think is something I always admire. She would walk into a room and all eyes were on her, and it's not just because of the level of fame - there was an incredible charm that went with it."