The King’s “constitutionally unwise” meeting with EU chief Ursula von der Leyen has angered unionists as Rishi Sunak seeks their support over the new post-Brexit deal on Northern Ireland.
Leading Conservative Brexiteer Jacob Rees-Mogg said it was wrong to involve Charles in the “immediate political controversy” on the day the Prime Minister will sign a new agreement with her.
Baroness Arlene Foster, the former Democratic Unionist Party (DUP) leader and first minister of Northern Ireland, said the meeting in Windsor Castle was “crass and will go down very badly”.
Buckingham Palace said Charles was acting on “the Government’s advice”. Downing Street said it was “fundamentally” a decision for the King.
Charles and the European Commission president will sit down for tea late on Monday after she is expected to sign off on a long-awaited Northern Ireland Protocol agreement with Rishi Sunak.
Mr Rees-Mogg, a former Cabinet minister, said: “It is surprising that The King will meet Ursula von der Leyen today as it antagonises the people the Prime Minister needs to conciliate.
“It is also constitutionally unwise to involve the King in a matter of immediate political controversy.”
Baroness Foster added: “I cannot quite believe that No 10 would ask HM the King to become involved in the finalising of a deal as controversial as this one. 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.”
The announcement of Monday’s meeting came despite warnings that it could draw the King, who as head of state must remain politically neutral, into the process of the UK and EU agreeing a deal or be seen as tacitly endorsing it.
Downing Street has defended the move to advise the King to meet Ms von der Leyen, saying Mr Sunak “fundamentally” believes the final decision was for Charles.
“He firmly believes it’s for the King to make those decisions,” the Prime Minister’s official spokesman said.
He compared the von der Leyen meeting to Charles talking to Poland’s Andrzej Duda or Ukraine’s President Volodymyr Zelensky.
“It’s not uncommon for his majesty to accept invitations to meet certain leaders, he has met President Duda and President Zelensky recently. He is meeting with the president of the EU today,” the spokesman said.
Asked why the final protocol talks were taking place in Windsor, he said: “There are a number of occasions when these sorts of talks have been held in significant locations, this is no different.”
Conservatives were among those voicing their criticism of the meeting before it was even confirmed, following suggestions the deal would be called the “Windsor Agreement”.
And Sammy Wilson, the DUP’s chief whip said the expected meeting would risk “dragging the King into a hugely controversial political issue”.
Topics up for discussion between Charles and the EU chief include climate change and the Russian invasion of Ukraine, though it was unknown if they will discuss Northern Ireland.
A Buckingham Palace spokesman said: “The King is pleased to meet any world leader if they are visiting Britain and it is the Government’s advice that he should do so.”
Charles and Ms von der Leyen will meet at Windsor Castle once her commitments elsewhere have been fulfilled.
European Commission deputy chief spokeswoman Dana Spinant insisted the meeting was “not part of this process” to secure a deal.
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