LONDON — King Charles III had nothing to do with the Northern Ireland trade agreement unveiled on Monday by Britain and the European Union. But one could be forgiven for thinking that he had put his royal imprimatur on the deal.
It is called the Windsor Framework, which happens to be the king’s family name. It was sealed at a luxury hotel in Windsor, west of London, where he has a castle. And it was there, at Windsor Castle, that Charles welcomed one of the negotiators, Ursula von der Leyen, the president of the European Commission, for tea just minutes after she and Prime Minister Rishi Sunak presented the deal to the world.
That courtesy call, and the resulting photo of a smiling king appearing to celebrate his guest, prompted angry recrimination from critics, who said the government improperly recruited King Charles to be an ally in one of the most divisive issues in British politics. By tradition, Britain’s constitutional monarch steers clear of politics, to say nothing of the noxious crosswinds of Brexit.
Buckingham Palace and Downing Street appeared at odds over who had initiated the meeting with Ms. von der Leyen. The palace said the king was acting on the “government’s advice,” while a spokesman for the prime minister said Mr. Sunak “firmly believes it’s for the king to make those decisions.”
To many, this may seem a trivial dispute over protocol. But historians noted that the British monarch is a resonant figure to unionists in Northern Ireland, who are the main holdouts to the trade agreement. Unionists favor keeping the North part of the United Kingdom, and profess allegiance to the British monarch. By giving the king such a conspicuous role in the finalizing of the agreement, and by wrapping the deal in the Windsor name, some observers said the government was making it harder for the unionists to reject it.
“Calling it the Windsor Agreement, the government tried to imply that he supports it,” said Vernon Bogdanor, an authority on the constitutional monarchy at Kings College London. “I think the king has been put in a very embarrassing position.”
Other royal watchers were less willing to let Charles off the hook for his enthusiastic role in the day’s events. They said the king and his courtiers showed poor judgment in agreeing to meet Ms. von der Leyen because of Charles’s desire to appear statesmanlike, to be in the thick of things and to be on the right side of history.
“He could have met her today, tomorrow, or next week,” said Peter Hunt, a former royal correspondent for the BBC. “It is the responsibility of him and his people to decide whether the moment is right, and this one wasn’t. Their judgment was clouded because they were flattered by the prospect of being in the spotlight.”
Monarchs regularly meet foreign leaders at the request of the government. Sometimes those leaders are less than savory: Queen Elizabeth II met Nicolae Ceausescu, the reviled dictator of Romania, and President Vladimir V. Putin of Russia, who once kept her waiting. Charles hosted a banquet for President Cyril Ramaphosa of South Africa, a week before he faced an impeachment vote on charges of money laundering.
“We don’t know if he argued against it or not,” Professor Bogdanor said of the king’s meeting with Ms. von der Leyen, “but either way, he had to go along with it.”
What makes this episode murkier is that Charles, by instinct and experience, would be likely to embrace the Windsor Framework. The deal aims to reinforce the United Kingdom and reset relations between Britain and the European Union. While the king has never publicly opined on Brexit, he gave a hint of his views in a speech to the German Parliament in 2020, when he said, “no country is really an island.”
Moreover, Charles is a man of passionate political convictions who embraces causes, from climate change to organic farming, in a way that his mother, Queen Elizabeth II, never did. He was frustrated, people with ties to the palace said, when the government of Mr. Sunak’s predecessor, Liz Truss, advised him not to attend the United Nations climate summit in Sharm el Sheikh, Egypt, last fall.
Charles acknowledged after he ascended the throne in September that he would have to give up any political engagement. He did not protest the government’s advice to skip the climate conference but instead threw a glittering reception at Buckingham Palace before the event; the guest list included John Kerry, President Biden’s climate envoy, and Stella McCartney, the fashion designer and a daughter of Paul McCartney, who has promoted sustainable manufacturing.
Climate change was one of the topics on the agenda at the king’s meeting with Ms. von der Leyen, according to the palace, as was Russia’s war in Ukraine. Charles welcomed President Volodymyr Zelensky of Ukraine to Buckingham Palace earlier this month when he visited London to address Parliament and make an appeal for Britain to supply the Ukrainian air force with fighter planes.
Taking note of that visit, the government brushed aside questions about the king’s meeting with Ms. von der Leyen. “Ursula von der Leyen is a very senior international representative,” the foreign secretary, James Cleverly, said to LBC radio. “It is therefore not unusual as part of our hospitality to international guests to facilitate a meeting.”
But Britain’s support for Ukraine is widely accepted by the political establishment. The post-Brexit trade status for Northern Ireland, on the other hand, is the subject of almost theological debate among hard-line Brexiteers in Mr. Sunak’s Conservative Party and unionist politicians in Northern Ireland.
Both groups expressed unhappiness with the visible presence of the king. Jacob Rees-Mogg, a euro-skeptic Conservative lawmaker and former cabinet minister, told the broadcaster GB News that “the sovereign should only be involved when things have been completed and accepted.”
Arlene Foster, a former first minister of Northern Ireland and leader of the Democratic Unionist Party, said on Twitter, “It’s crass and will go down very badly in NI. We must remember this is not the King’s decision but the Government who it appears are tone deaf.”
Some of that uneasiness may reflect the importance of the monarchy to the unionists. Professor Bogdanor said that unionists tended to view their allegiance to the king in more contractual terms than people in England, for whom fealty was generally automatic. The heart of that contract, he said, was preserving the union.
“The king has enormous resonance in Northern Ireland,” he said. “The king is what separates unionists from nationalists.”
And yet Charles has been on the throne for less than seven months. His mother reigned for 70 years, making her an iconic figure in Belfast, where her portrait appears on murals and walls in the city’s unionist neighborhoods. Some experts predicted that the debate over the king’s role would fade away quickly, as the unionists busied themselves with a gimlet-eyed reading of the text of the Windsor Agreement.
“If it had been the queen, it might have been important,” said Katy Hayward, a professor of politics at Queen’s University in Belfast. “But I haven’t seen or heard anything to indicate it raised more than an eyebrow.”