A former French ambassador to the UK said it would have been “impossible” for President Emmanuel Macron to have hosted Charles during civil unrest in the country.
The King’s first state visit since taking the throne from his late mother the Queen was postponed due to the eruption of violent demonstrations across France over forced-through pension reforms.
Sylvie Bermann, who served as Paris’ ambassador to Britain between 2014 and 2017, said Mr Macron wanted the visit to go ahead “until the last minute” before realising the situation was untenable.
The former diplomat said a planned state banquet at the Palace of Versailles for Charles and Camilla would “not have given a good image”.
Lord Ricketts, a former national security adviser, said the lavish Versailles dinner would have had “echoes” of the French revolution if it had gone ahead during public outcry at Mr Macron’s decision to push back the national retirement age.
Police have been injured in protests that have seen hundreds arrested, with ugly scenes of rubbish build-ups and arson attacks.
It is reported that more than a million people took to the streets across France on Thursday during the biggest demonstrations since Mr Macron pushed through a Bill raising the retirement age from 62 to 64 without a vote in the National Assembly, the lower house of the French parliament.
Images of the town hall of Bordeaux – a city the royal couple were due to visit – set alight by protesters on Thursday evening were symbolic of the fury felt by some at the reforms.
Mr Macron is said to have spoken with the King to relay the reasons for needing to postpone the scheduled trip in a move that is being seen as embarrassing for the French leader.
At a press conference on Friday, the president said the four-day state visit was likely to be rescheduled for the beginning of summer.
Ms Bermann told BBC Radio 4’s Today programme it was a “real frustration” to have to delay Charles’ visit after a breakthrough in cross-Channel relations.
Tensions arose between London and Paris during Boris Johnson’s premiership due to arguments over Brexit, Covid vaccines and the Aukus defence deal between the UK, US and Australia that usurped a submarine-building accord signed by France and Canberra.
But since Rishi Sunak became Prime Minister in October, relations have been noticeably warmer, with a UK-France summit earlier this month leading to an agreement to increase joint efforts to prevent migrants crossing the Channel to Britain in small boats.
The state visit was aimed at further strengthening ties between Britain and its continental neighbour using the “soft diplomacy” deployed by members of the royal family.
Ms Bermann said: “It is a real frustration and I think until the last minute the president wanted to maintain the visit.
“But it was impossible, not only because of security but because it wouldn’t have been the best conditions.
“It is true that the dinner in Versailles would not have given a good image while there is unrest in France.”
Crossbench peer Lord Ricketts, who was the UK’s ambassador to France during the Queen’s final state visit to the country in 2014, told Today the violent demonstrations seen on Thursday were what “probably tipped the balance”.
He speculated that Buckingham Palace was likely “very happy” to have accepted the Elysee Palace’s advice not to travel given the country’s unrest.
“Much better that it should be postponed to a quieter time than it be overshadowed by a massive security situation and potentially awkward incidents,” Lord Ricketts said.
He added: “I think when the state visit was planned, it was going to be the culmination of a period of real improvement in UK-French relations, marked by the summit between Rishi Sunak and Macron a couple of weeks ago.
“The fact that there are now these violent protests which seem to be growing made, in particular, the idea of a banquet in Versailles a particularly bad idea.
“That had all kinds of echoes from the past going back to the revolution.
“Bordeaux looked to be difficult as well for the visit the King was planning to make.
“So, as it turned out, the circumstances were not right, in which case it is right to postpone.”
The King and Queen Consort’s scheduled state visit to Germany, which had been due to take place after the French tour, is understood to be going ahead as planned.