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Earl Spencer has said he felt there was a "lightness" in the tone of the then-Prince Charles during a phone call following the death of his sister, Diana, Princess of Wales.

In an interview with the BBC's Laura Kuenssberg, he said he took a call at his home in Cape Town from Charles, who told him how he had broken the news to Princes William and Harry at Balmoral Castle.

"I felt there was a sort of giddy tone," Earl Spencer told the BBC. "I'd had a lot of calls that day from people who cared, who were stunned... and I just felt there was a lightness in his tone about Diana's death that really jarred with me."

Buckingham Palace released a rare statement on Wednesday in response to claims made by Earl Spencer in his book Swan Song: Diana, My Sister, which is due to be published on Tuesday.

It said the King was "mindful that the pain of fraternal grief can cloud reason, affect judgement and colour memory in ways others do not recognise, even many years after such a loss".

The full interview, Princess Diana: My Sister's Story, is available on BBC iPlayer and will be broadcast on BBC One at 18:30 BST on Sunday.

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