King Charles III’s address to the US Congress last week was a “high stakes” occasion, a senior royal aide said, but one that reflected the monarch’s personal “conscience”.
In the state visit speech, in which the King urged US lawmakers to defend Ukraine and back Nato, the aide said the remarks showed “how much he personally cares”.
The speech has been widely praised for its diplomatic skill in pressing US President Donald Trump to uphold democratic values in a “volatile world”.
Buckingham Palace has been reflecting on what it called the biggest diplomatic challenge of the King’s reign.
The visit came against a backdrop of political tension between the UK and the US, most recently over the UK government’s decision not to get involved in the Iran conflict.
Speaking to Congress on Tuesday, the King mixed humour and charm with a surprisingly direct appeal for US support for democratic principles.
“Everything that is in that speech is an observable fact. And so, I think we felt very comfortable with the King speaking as he did,” the royal aide said, adding that the monarch was guided by a sense of “truth” and “conscience”.
The address was warmly received in the Capitol, earning the King 12 standing ovations.
On the personal chemistry between the King and the US president, the aide said relations were more positive than might have been expected, given differences on some policy issues.
“They get on very well… It’s a pairing, sort of unlikely though it might be in many ways… I mean, given some of the issues that have presented themselves in the bilateral relationship, you’d think it might all be a bit tricky. But far from it. And the warmth that you see in public is absolutely the warmth you see in private. That meeting in the Oval Office, there was an awful lot of warmth and laughter,” the aide said.
Ahead of the trip, a diplomatic difficulty was that Mr Trump has been an enthusiastic admirer of the King and the monarchy while also criticising the UK’s prime minister and armed forces.
The state visit aimed to rebuild bridges between the UK and US beyond the focus on the royals.
“It’s not a competition between the King and the government,” the royal aide said. “The King is there to support the government, to help the government. It was at the government’s request, of course, that he undertook this visit.”
There were no press conferences during the state visit, but some diplomatic eyebrows were raised after Mr Trump appeared to suggest the King shared his views on the war with Iran.
At the state dinner, Mr Trump said: “We have militarily defeated that particular opponent, and we’re never going to let that opponent ever – Charles agrees with me even more than I do – we’re never going to let that opponent have a nuclear weapon.”
Buckingham Palace played down the remark, saying it aligned with the UK government’s stance on non-proliferation.
Later, the president continued to imply the King supported his Iran policy, saying: “If that were up to him, he would have probably helped us with Iran,” referring to talks with the “great King”. Buckingham Palace did not comment on that.
After leaving the US, the King travelled on to Bermuda.
Mr Trump said the visiting royals “got me to do something that nobody else was able to do, without hardly even asking”.
An opinion poll by YouGov, published on Saturday from a sample of 4,500 people, suggested the UK public viewed the King’s US performance positively: 74% said he had handled the state visit well, while 4% said he had handled it badly.
That marks a significant turnaround from polls taken before the trip, which showed many people wanted the visit called off and were sceptical about its value.
Andrew Lownie, author of a critical biography of Prince Andrew, noted the broad approval, saying: “What’s most astonishing is the reaction not just of monarchists but of British republicans. Given the public pessimism and foreboding that led up to the visit, this is a considerable triumph for the King,” he wrote in his Lownie Report newsletter.
In the New York Times, Maureen Dowd wrote: “The King deftly schooled Donald, and Donald took it because he has always been awed by the British royal family.”
The senior royal aide said: “What looked like risk and challenge was also a phenomenal opportunity. One that was grasped in both hands by the King.”