Prince Charles bombarded former British prime minister Tony Blair with letters on sensitive political issues which the ex-premier thought crossed the line, his former media chief said Saturday.
According to extracts from Alastair Campbell's diaries published in The Guardian newspaper, Blair thought the heir to the throne went too far in getting publicly involved on topics such as genetically-modified (GM) foods and fox hunting.
Blair, the prime minister from 1997 to 2007, thought Charles sometimes stepped over the constitutional boundaries historically respected by the royal family, the former Downing Street director of communications said.
As a constitutional monarch, the British sovereign is above political matters and never speaks publicly on them. Other senior royals take a similar line in order not to risk compromising her neutrality.
However, Charles, next in line to the throne, regularly expresses forthright views on the environment, architecture and traditional rural ways of life as he carves his own niche in his Prince of Wales role.
Blair even once said privately that Charles was "screwing us" by intervening on behalf of farmers during the foot and mouth crisis in 2001, Campbell said.
Charles also boycotted a 1999 banquet in honour of China's then president Jiang Zemin, which Blair reportedly regarded as "silly".
Charles' media operation had "clearly briefed that he had deliberately snubbed" the banquet and told Blair in writing: "I feel very strongly about it", Campbell recorded.
Blair asked Charles "whether he really thought we should have nothing to do with Jiang Zemin. He didn't really have an answer", Campbell wrote.
Campbell said that Blair thought Charles had been "really stung" by a 1999 speech attacking the "forces of conservatism".
"He said they (the royals) felt much more vulnerable than in reality they are. We know they still have the power to 'keep us in our place' but they don't always see it like that," the former spin doctor wrote.
"Tony Blair valued their regular private conversations and respects Prince Charles's right to speak up on important issues," he told The Guardian.
"But this was a period when it seemed Charles's media team was proactively and publicly setting them at odds on some of the Government's most difficult issues not just hunting, where the differences were well known, but GM food, China, and agriculture."
His diary entry for June 1 1999, shortly after the prince wrote an article on GM foods, appears to suggest Blair raised his concerns with Queen Elizabeth II.
The sovereign holds a weekly audience with the prime minister and the content is strictly confidential.
"TB saw the Queen and seemingly didn't push too hard re Charles but he was very pissed off," wrote Campbell.
Charles had told Blair he "cannot stay silent" in his opposition to GM food.
And on October 31 1999, Campbell recorded a meeting between Blair and Charles shortly after he took his eldest son Prince William fox-hunting in what was widely seen as a public challenge to the proposed ban.
"While publicly we stayed supportive, TB said Charles had to understand there were limits to the extent to which they could play politics with him," Campbell wrote.
"He said it was 90 minutes of pretty hard talk, not just about hunting."
Campbell listed a series of interventions by Charles which supposedly infuriated Blair, and lengthy handwritten letters on a range of topics.