The prime minister’s impeachment trial has been criticized after a meeting between the king and the leader of the European Union was cancelled.
European Commission President Ursula von der Leyen was expected to travel to Britain on Saturday amid speculation that a deal was close to fixing problems with the Northern Ireland Protocol.
The German politician was also due to meet the King at Windsor Castle, Sky News said.
There were talks about calling a possible protocol deal the “Windsor Agreement” after a meeting with Charles, the broadcaster said.
UK government sources confirmed that Ms von der Leyen’s trip was cancelled, but it is likely that Downing Street and Buckingham Palace worked together on the reported arrangements.
Rishi Sunak’s critics said the scheduled meeting cast doubt on his handling of the protocol negotiations.
Jacob Rees-Mogg, former business secretary and senior fellow at the Tory Eurosceptic European Research Group (ERG), told the PA news agency: “If there were a plan to bring in the King before there is an internal political agreement, it would border on the constitutional impropriety”.
Sunak is keen to secure the backing of not only his Conservative MPs but also the Democratic Unionist Party (DUP) for any protocol reforms as he seeks to restore power sharing in Belfast.
The DUP refuses to take part in Stormont’s cross-community delegate government in protest at the impact Brexit is having on trade between Northern Ireland and Great Britain.
Former DUP deputy leader Lord Dodds said meeting Ms von der Leyen would have politicized the monarch and argued that the reports “reinforce questions about the impeachment of number 10 over protocol.”
Sammy Wilson, a DUP MP, said any Windsor meeting with the EU leader would have been “a cynical use” of the King’s position and seen in unionist circles as the sovereign backing the deal.
He called the prime minister “naive” and accused him of “dragging the king into a highly controversial political issue.”
“The only conclusion we can come to is that he knows that in these negotiations he failed to achieve the goals he set for himself and his own party,” Wilson told Sky News about Sunak.
“He has also failed to keep the promises he had made to ourselves and now he was trying to get the King to do what he could for him.”
Baroness Hoey, a Brexit supporter from Northern Ireland and a former Labor MP, said any such meeting would have been “outrageous”.
UK government sources said that while Ms von der Leyen’s trip would no longer take place, it would not have been inappropriate for the King, as head of state, to meet a visiting European leader.
“It would be wrong to suggest that the King would be involved in anything remotely political,” a government source told PA.
Buckingham Palace had no comment.
Northern Ireland Labor Secretary Peter Kyle said Downing Street should have realized that using the King would have “constitutional implications” and be “very insensitive to Northern Ireland politics”.
“It’s certainly nothing we should involve Her Majesty in,” he told Sky.
No 10 said Mr Sunak will spend the weekend talking to “relevant stakeholders” as he seeks to obtain a protocol agreement on the line.
Downing Street said “intensive negotiations” were still taking place with Brussels.
Multiple reports suggest the UK-EU deal is almost done, with Sunak holding off on an announcement until he is sure it will be accepted.
The protocol, signed by former Prime Minister Boris Johnson in 2020, was designed to avoid a hard border with Ireland after Brexit by keeping Northern Ireland in the EU’s single market.
But the treaty has outraged unionists because of the trade barriers it created between Northern Ireland and the rest of the UK.
According to The Times, the current offer on the table would mean a revised protocol, which would remove almost all checks and most paperwork on goods crossing the Irish Sea.
The newspaper said the deal would also mean control over the VAT rate and state aid policy would rest with Westminster instead of Brussels for the first time since Brexit was enacted.
Speculation that number 10 is preparing to confirm a deal to fix the protocol intensified on Friday after a Downing Street source said “good progress” had been made during a phone call between the prime minister and the commission chairman.
Any announcement of a deal is expected to set up a potential showdown with Brexit hardliners, with the prime minister vowing that MPs will have the chance to “express” their views on the new terms.
The DUP has issued seven tests to win its backing for any deal, including tackling what it calls Northern Ireland’s “democratic deficit” which is subject to EU rules without having a say in them.
The Daily Telegraph, which said there could be a breakthrough over the weekend, said it was understood the DUP would be given a seat at the negotiating table when the EU is considering new laws applicable to Northern Ireland.