They say their action is in retaliation for the British occupation of the Falkland Islands, but also admit it is a bit of a joke.

The BBC's Carrissa Bub spoke to the invaders

The office of 'King Orelie-Antoine I' said its marines stamped the name of the Kingdom of Patagonia and hoisted its flag on the largest of the Minquiers rocks.

"At dawn on Sunday, a light naval unit of the Patagonia Fleet landed on the formerly British Minquiers archipelago and hoisted the royal blue-white-green flag to replace the British flag which can be honourably returned to her British Majesty's embassy in Paris," it said.

The statement said this was the second "royal" landing on the rocks after a unit claimed possession on 1 June 1984 "to respond to Britain's unacceptable and prolonged occupation of the Malouines (Falkland) Islands, a territory of Patagonia".

Eccentric writer

Most of the Minquiers rocks, south of the Channel island of Jersey, are under water at high tide. The International Court in The Hague in 1953 turned down a French claim and confirmed British sovereignty.

King Orelie-Antoine - an eccentric writer whose real name is Jean Raspail - says he took over France's rights to the rocks.

He claims to be a relative of a French adventurer who declared a short-lived 'Kingdom of Patagonia' on Argentine territory in the 19th century.

Tim Livesey from the British Embassy in Paris: "It's not the first time"

Tim Livesey of the British Embassy in Paris said they would be contacting Mr Raspail to recover the flag that was taken from the rocks of Minquiers and replaced with the blue, white and green flag of Patagonia.

Mr Livesey said: "We have had some contact with Mr Raspail and we are hoping to recover the flag that he says he took from the islands at some point later this week.

"Our contact was extremely amicable. I think this is one of human interest stories that keeps British and French relations from being too stodgy."

Mr Raspail, 73, says that he will hand over the flag but only if he can return it on neutral ground - a Paris bar.