ARTICLE AD BOX
By Sean Coughlan
Royal correspondent
King Charles will meet EU chief Ursula von der Leyen for tea at Windsor Castle, after she was due to meet Rishi Sunak to agree a Northern Ireland Brexit deal.
Buckingham Palace said the meeting had been arranged on the advice of the government.
Number 10 said it was "fundamentally" a decision for the King.
But there have been warnings against drawing the monarch into a contentious political dispute.
Conservative MP Jacob Rees-Mogg, a Brexiteer and former cabinet minister, said it was "constitutionally unwise to involve the King in a matter of immediate political controversy".
Sammy Wilson, chief whip of the Democratic Unionist Party, said the meeting would risk "dragging the King into a hugely controversial political issue".
But the prime minister's official spokesman likened the meeting with Ms von der Leyen to the King's other recent meetings with visiting international dignitaries such as Polish President Andrzej Duda or Ukrainian President Volodymyr Zelensky.
"It's for the King to make those decisions," said the Number 10 spokesman.
"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," said a palace spokesman.
At around 14:20 GMT, ahead of the meeting, a senior Government source told the BBC a new Brexit agreement for Northern Ireland had been reached.
The EU sought to distance the Windsor meeting from political negotiations, saying the meeting between the King and the European Commission president was "separate" and "not part" of the talks over the Northern Ireland protocol.
Buckingham Palace sources emphasised that this was a regular meeting between the King and a visiting international leader and would build on other previous meetings between the King and Ms von der Leyen.
The Windsor Castle meeting, where tea will be served and photographs taken, was described in terms of a wider agenda, such as discussions about climate change and Ukraine.