Charles had planned a three-day visit to France in late March in what would have been his first state visit since succeeding his late mother, Queen Elizabeth, as British monarch in September.

But the visit was cancelled after social unrest over President Emmanuel Macron's new pension law erupted into some of the worst street violence seen in years across the country.

Instead, he visited Germany on his first overseas trip as king.

Buckingham Palace did not immediately have a comment on the report. Macron's office did not immediately respond to request for comment.

The agenda for the March visit had included a state banquet at the old royal palace at Versailles and a visit to the legendary Bordeaux wine-growing region. Charles had also been due to lay a wreath along with Macron at the Arc de Triomphe.

Charles had also been due to address senators and members of the National Assembly as part of a tour designed to celebrate Britain's ties with key European powers after its 2016 vote to leave the European Union.

Both Buckingham Palace and Macron said in March they looked forward to rescheduling the postponed trip future when new dates could be found.

(Reporting by Geert De Clercq, Jean-Michel Belot and Michel Rose in Paris and Farouq Suleiman in London; editing by Richard Lough, Kirsten Donovan, Gareth Jones)