LONDON — It was June 2019, and the president of the United States was taking tea with the future British king. 

The meeting between Donald Trump and then Prince Charles was scheduled to last 15 minutes. It stretched to an hour and a half.  

Trump could barely get a word in edgeways. Charles did “most of the talking,” the president told a TV interviewer the day after they met.  

One topic dominated. “He is …” Trump said, hesitating momentarily, “… he is really into climate change.” 

Without global action on the climate, Charles wrote back in 2010, the world is on “the brink of potential disaster.” At the London royal residence Clarence House during Trump’s first U.K. state visit, face-to-face with its most powerful inhabitant, Charles decided to speak on behalf of the planet. 

It was tea with a side of climate catastrophe.  

Six years on, the stage is set for Charles — now king — to try to sway the president again. A second term Trump — bolder, brasher, and no less destructive to global efforts to tackle climate change — is heading back to the U.K. for an unprecedented second state visit and to another meeting with the king. They meet at Windsor Castle on Wednesday. 

In the years between the two visits — with extreme weather events, wildfires and flooding increasingly attributed to a changing climate — Charles’ convictions have only strengthened, say those who know him well. 

“His views have not changed and will not change. If anything I think he feels it, probably, more strongly than ever,” said the broadcaster Jonathan Dimbleby, a friend and biographer of the king. “It seems self-evident to me, therefore, that he would regard President Trump’s attitude towards climate change and the environment as potentially calamitous.”  

But stakes are higher for the king in 2025 than in 2019. The meeting represents an extraordinary influencing opportunity for a monarch who has spent his life deploying “soft power” in the service of cherished environmental causes. But now he is head of state, any overtly political conversation about climate change risks stress-testing the U.K.’s constitutional settlement between government and monarch. 

Charles has a duty, says constitutional expert Craig Prescott, to “support the [elected] government of the day in what they want to achieve in foreign relations.” 

And “in a broad sense,” he added, “that means ‘getting on the good side of Trump.’” 

Labour’s focus on an ambitious green transition, though, gives the king some leeway to speak in favor of international climate action.  Both Dimbleby and Ian Skelly, a former speechwriter for Charles who co-wrote his 2010 book Harmony, expect him to do exactly that. 

“I would be astonished if in this meeting, as at the last meeting , he does not raise the issue of climate change and biodiversity in any chance he has to speak privately to Trump,” said Dimbleby.  

The king will be “diplomatic,” Dimbleby added, and would heed his “constitutional duty,” avoiding “saying anything that will allow Trump to think there is a bus ticket between him and the British government. … But he won’t avoid the issue. He cares about it too much.” 

“He knows exactly where the limits are,” said Skelly. “He’s not going to start banging the table or anything. … He will outline his concerns in general terms, I have no doubt about that — and perhaps warn the most powerful person in the world about the dangers of doing nothing.” 

Buckingham Palace and Downing Street declined to comment when asked whether the king would raise climate with Trump, or whether this has been discussed in preparations for the state visit. 

Have you read my book, Mr. President? 

In the time since that tea at Clarence House, the President has shown no sign that Charles’ entreaties on the part of the planet had any impact. (And they didn’t have much effect at the time, by one insider’s account. Trump complained the conversation “had been terrible,” wrote former White House Press Secretary Stephanie Grisham in her memoir.  “‘Nothing but climate change,’ he groused, rolling his eyes.”) 

The U.S. has once again withdrawn from the Paris climate accords. Trump’s Department of Energy has rejected established climate science. America’s fossil fuel firms and investors — some of whom helped Trump get elected — have been invited to “Drill, baby, drill.” 

With America out of the fight, the world’s chances of avoiding the direst consequences of climate change have taken a serious blow. 

Charles, on the other hand, has only grown more convinced that climate change, unchecked, will cause “inevitable catastrophes,” as he put it in Harmony, his cri-de-coeur on saving the planet. 

Dimbleby predicted that, this time around, one subtle way allowing the king to make his point would be to gift Trump a copy of that book — a treatise on environmentalism, traditional wisdom and sustainability that diagnoses “a spiritual void” in modern societies, a void which has “opened the way for what many people see as an excessive personal focus.” 

“I’m sure [the king] won’t let [Trump] out of his sight before giving him a copy,” said Dimbleby. Chinese Premier (and Trump’s main geopolitical rival) Xi Jinping already has a copy, said Skelly. 

But the meeting comes at a time when Prime Minister Keir Starmer — boxed in politically by the need to keep the U.S. on side for the sake of trade, Ukraine and European security — has avoided openly criticizing the Trump administration’s attacks on climate science or its embrace of fossil fuels. 

His government will not want the king to say or do anything that upsets transatlantic relations. Even when the president, sitting next to Starmer, trashed wind energy ­— the main pillar of U.K. decarbonization plans — on a July visit to his Turnberry golf course in Scotland, the prime minister mustered no defense beyond quietly insisting the U.K. was pursuing a “mix” of energy sources. 

If Trump starts railing against windmills again in his chat to the king, he might get a (slightly) more robust response, predicted Skelly. “The response to that will be: ‘What else are we going to do without destroying the Earth?’ That’s the question he’ll come back with, I’d imagine.” 

How to talk to Trump about climate 

Some who have worked with Trump think that, because of the unique place Britain and the royals occupy in his worldview, Charles stands a better chance than most in getting the president to listen. 

“President Trump isn’t going to become an environmentalist over a cup of tea with the king. But I think he’ll definitely hear him out — in a way that maybe he wouldn’t with other folks,” said Michael Martins, founder of the firm Overton Advisory, who was a political and economic specialist at the U.S. embassy in London during the last state visit. 

“He likes the pageantry. He likes the optics of it. … Engaging with a king, Trump will feel he’s on the same footing. He will give him more of a hearing than if it was, I don’t know … Ed Miliband.” 

Trump has even declared his “love” for Charles. 

The royal admiration comes from Trump’s mother. Scottish-born Mary Anne Trump “loved the Queen,” Trump said in July. The ratings-obsessed president appears to consider the late monarch the ultimate TV star. “Whenever the queen was on television, [my mother] wanted to watch,” he said during July’s Turnberry visit.   

The king could benefit from an emotional link to First Lady Melania Trump, too. She was present at the 2019 meeting and sat next to Charles at the state banquet that year. In her 2024 memoir, Melania says they “engaged in an interesting conversation about his deep-rooted commitment to environmental conservation.” 

She and Trump “exchange letters with King Charles to this day,” Melania wrote.

Taking tea at the end of the world 

The king will have plenty of chances to make his case.  

A state visit provides “quite a lot of time to talk” for monarch and president, said one former senior British government official, granted anonymity to discuss the royals and their relationship with government. 

There will be a state banquet plus at least one private meeting in between, they said. Charles may also be able to sneak some choice phrases into any speech he gives at the banquet.

The king receives regular briefing papers from the Foreign Office. As the meeting looms, the same person suggested, he may be preparing thoughts on how to combine a lifetime’s campaigning and reading with those briefings, to shape the opportunity to lobby a president. 

“He will be reading his foreign policy material with even more interest than normal. He will probably be thinking about whether there is any way in which he can pitch his arguments to Trump that will shift him — a little bit — toward putting his shoulder to the climate change wheel,” the former senior official said.   

“He won’t say: ‘You, America, should be doing stuff.’ He will say, ‘Internationally I think it is important we make progress on this and we need to be more ambitious.’ Or he might express concern about some of the impacts of climate change on global weather and all these extreme weather events.” 

However he approaches it, 2019 showed how tough it is to move the dial. 

After that conversation, Trump told broadcaster Piers Morgan that he thought Charles’ views were “great” and that he had “totally listened to him.” But then he demonstrated that — on the crucial points of how fossil fuels, carbon emissions and climate change are affecting the planet — he totally hadn’t.   

“He wants to make sure future generations have climate that is good climate, as opposed to a disaster,” Trump said. “And I agree,” he added, before promptly pivoting to an apparent non-sequitur about the U.S. having “crystal clean” water.

It was a typically Trumpian obfuscation. Asked about the king’s views during the Turnberry visit, Trump said: “Every time I met with him, he talked about the environment, how important it is. I’m all for it. I think that’s great.” 

In nearly the same breath, he ranted about wind energy being “a disaster.” 

Good luck, Charlie 

“It is difficult, if not impossible, to see [Trump] change his views on climate change, because they’re not informed by his understanding of the science or consequences, but rather by naked politics,” said leading U.S. climate scientist Michael Mann in emailed remarks.  

And Trump will come to the meeting prepared, said Martins, the former U.S. Embassy official.

“Trump will receive the full briefing on the king’s views on environment. He won’t be going into that blind. He’ll know exactly what the king has said over his career and what his views are on it and how it affects American interests. I don’t anticipate him being surprised by anything the king says.”  

He added: “Bashing net zero and President Biden … gets [Trump] political wins.”   

To Charles’ long-standing domestic critics, it all highlights the pointlessness of his position. 

“He is bound by these constitutional expectations that he does nothing that will upset the apple cart [in U.K./U.S. relations],” said Graham Smith, chief executive of campaign group Republic, which calls for the abolition of the monarchy. “If he was elected, he’d have a lot more freedom to say what he actually wants.” 

“Soft power is a highly questionable concept,” added Smith. It’s only useful, he argued, when backed by something Charles lacks and Trump has by the bucket-load: “Hard power.” 

And time may be running out for Charles to deploy even soft power in the climate fight.  

Trump’s chief U.K. political ally is Nigel Farage, whose anti-net-zero Reform UK currently lead opinion polls. If British voters pick Reform at the next election, Charles’ potential advocacy would be restrained by a government opposed to action on climate change. 

So how far will Charles go to seize his moment? 

He wrote in Harmony: “If we continue to be deluded by the increasingly irresponsible clamour of sceptical voices that doubt man-made climate change, it will soon be too late to reverse the chaos we have helped to unleash.” He feared “failing in my duty to future generations and to the Earth itself” if he did not speak up.  

Skelly, the former speechwriter who co-wrote the book, predicted that Charles would walk a fine diplomatic line — but was “not someone to sit on his hands or to remain silent.”  

“He was warning about these things 30 years ago and nobody was listening. … He feels increasingly frustrated that time is running out.  

“I’d love to be a fly on the wall — because it will be a fascinating conversation.”