Dame Helen Mirren has spoken of her relief that she sent a letter to the Queen while she was shooting her 2006 film about the monarch.

The drama focused on the death of Diana, Princess of Wales, and whether the Queen would return to London to pay tribute amid growing public pressure.

Dame Helen, 76 who was raised in Leigh and went to St Bernard’s in Westcliff, said she had quickly realised she was dealing with a sensitive moment in the Queen’s life and decided to contact her.

Read more >>> Dame Helen Mirren helps historic Leigh Dunkirk cockle ship

She told Radio Times: “I realised we were investigating a profoundly painful part of her life, so I wrote to her.

“I said: ‘We are doing this film. We are investigating a very difficult time in your life. I hope it’s not too awful for you’.

“I just said that in my research I found myself with a growing respect for her, and I just wanted to say that. I was very relieved subsequently that I had written that letter.”

Dame Helen said that while preparing for the film she had thought of the Queen “as a submarine, with a periscope.”

Read the full interview in Radio Times, out now.