Earl Spencer insists 'I'm telling the truth' about Charles saying Diana would be 'forgotten' and calls it 'monstrous' in BBC interview

Earl Spencer has insisted he is 'telling the truth' about a phone call with Prince Charles in the days following the death of his sister Princess Diana.In his new autobiography - exclusively serialised in the Daily Mail - the Earl claims Charles told him 'we'll forget her [Diana] soon enough' during an argument over William and Harry's involvement in her funeral. Buckingham Palace hit back with a strongly worded response, suggesting that grief had clouded Earl Spencer's 'reason, judgment and memory'. But the Earl has doubled down on the account given in his book 'Swan Song: Diana, My Sister', saying 'I can tell you here and now, those are exactly the words he said.'Speaking to the BBC's Laura Kuenssberg from his Althorp estate in Northamptonshire, Earl Spencer said he had told friends and family of Charles' alleged words at the time, labelling them 'monstrous'.'I've only ever had two calls on the line with Prince Charles at any stage of my life,' he said.'I was hyper alert to what he was saying and those are precisely the words that he said and I promise that to you now.'Alluding to the Palace's statement, he added: 'Genuinely, that is what he said. I don't hear him saying he didn't say that.' Earl Spencer has insisted he is 'telling the truth' about remarks made by the then-Prince Charles in the wake of Princess Diana's death His explosive memoir - Swan Song: Diana, My Sister - is one of the most anticipated books of the year and is due to be released next weekThe earl claims Charles 'went ballistic' and 'ranted for a while' after he tried to tell the future King that Diana would not have wanted William and Harry to walk in her procession.'And then he stopped and I thought, oh now, now he's gonna pull himself together and say something more appropriate,' he said.'And then, he said, "we'll forget her soon enough".' Earl Spencer added that the remark 'stunned' him, and that he hung up.The book's first astonishing extract made headlines around the world and is splitting society, with rival camps backing either side.In the first extract, published online yesterday and in today's Daily Mail, the earl claims:The late Queen dramatically offered to restore Princess Diana's royal title on the day of her funeral;Diana told her father she could not go through with the marriage to Prince Charles a month before the wedding – but he told her it was 'impossible to pull out';The day before the wedding Charles told Diana that while he was happy to marry her, he was not in love with her;Diana was so unhappy that she considered suicide and drove herself 'more than once' to Beachy Head cliffs in East Sussex;Charles sounded 'giddily elated – like a lottery winner' shortly after Diana's death.Announcing the book last month, Earl Spencer said that, ahead of the 30th anniversary of Diana's death next year, he wanted to write down his own thoughts and memories 'rather than having the discomfort of again reading the opinions of others'.Prince Harry and Prince William, aged 12 and 15, ultimately did walk behind Diana's coffin in her funeral procession in September 1997 alongside Charles, Prince Philip and Earl Spencer. Prince Harry stands between Earl Spencer and Prince Charles outside Westminster Abbey during the funeral procession for Princess Diana on September 6, 1997Harry would later tell Newsweek magazine of the decision: 'My mother had just died and I had to walk a long way behind her coffin, surrounded by thousands of people watching me while millions more did on television.'I don’t think any child should be asked to do that, under any circumstances. I don’t think it would happen today.'The Duke of Sussex, newly returned to the UK with his wife Meghan and their two children, is 'aware' of the book but has not read it, sources have told the Mail.He ignored questions from reporters about it last night as he attended the inaugural Invictus Spirit Awards at the historic Old Royal Naval College in Greenwich.Swan Song: Diana, My Sister is due to be published next week.However, several copies of the book were stolen from a lorry parked in a lay-by in the Netherlands earlier this week. The tomes had been wrapped in black plastic to hide their contents, but publishing insiders believe they may have been deliberately targeted in an audacious bid to steal them before the official release.Read part one of our exclusive serialisation of Swan Song: Diana, My Sister - the searing memoir that has started a war of words with the King - here Read part two: Earl Spencer criticises the royals' 'lack of obvious care' for Prince Harry on the day of his mother Diana's funeral