A letter Prince Charles wrote to an old friend just days after he and Diana officially separated is coming to auction at Dominic Winter.

It’s written on paper headed HM Yacht Britannia and dated December 11, 1992. 

Charles writes thanking Dudley Poplak for a “greatly heartening” letter.

Prince Charles and Princess Diana separated in 1992 

He also vents his frustration at the way he is portrayed in the media: “Perhaps they will appreciate the things I try to do after I am dead..!

“The trouble is that, at the time, it can be pretty awful having to live through all the misinterpretation and the flak put up by those who stand for the purely materialist values.

“On the other hand, perhaps it is part of the test that I have to go through in order to come out the other side, having been tempered in the fire...”

The lot is valued at £300-400 ($387-516).

Another letter from Charles, dating to 1988 and addressed to architect Vernon Russell Smith, carries an identical estimate. 

It was written after the broadcast of Charles’ controversial documentary A Vision Of Britain, in which he revealed his intense dislike of modern architecture.

He writes: “I was trying to strike a blow for the ‘ordinary bloke's’ point of view and hope it will have encouraged some people to pluck up courage to call the experts' bluff!”

Chris Albury, auctioneer and senior valuer at Dominic Winter Auctioneers, said: “It is interesting to read his firm belief that he was giving voice to the 'ordinary bloke' while realising history will judge him on his views later.

“It is 30 years since he wrote this letter and his views continue to draw praise and outrage in equal measure…

“Even more unusual is to have a very personal and revealing letter from Prince Charles candidly expressing his pain and frustrations, too.”

The sale will take place on June 14 in London. 

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