It is “non-negotiable and undeniable” that the Falkland Islands are British, Grant Shapps has insisted, in the wake of demands from Argentina’s president-elect for diplomatic talks.

The Union Flag flies over the British War Cemetery at San Carlos, Falkland Islands -

Mr Shapps, the Defence Secretary, noted the Government had sent a new Royal Navy ship back to the islands, which were invaded by Argentina in 1982 before their liberation by British forces.

Javier Milei, who won a landslide victory in the Argentinian election on Sunday, has previously asserted his country’s sovereignty over the Falklands, arguing in the final television debate of the campaign that “every effort” must be made to reclaim the territory.

But in a tweet reasserting the Falklands’ status as a British overseas territory, Mr Shapps said:

Mr Shapps was referring to the results of a referendum in 2013 in which just three out of 1,516 islanders rejected remaining as an overseas territory of the United Kingdom.

The Ministry of Defence (MoD) confirmed on Monday that HMS Medway, a Royal Navy patrol ship, had completed its nine months in the Falklands and handed patrol duty back to HMS Forth, its sister ship.

HMS Forth, which has spent most of this year in Gibraltar, is central to the Falklands mission, which the MoD said was focused on “reassurance to and support for the island community”.

During the final television debate of the campaign, Mr Milei said: “What do I propose? Argentina’s sovereignty over the Malvinas Islands is non-negotiable. The Malvinas are Argentine.

“Now we have to see how we are going to get them back. It is clear that the war option is not a solution. We had a war - that we lost - and now we have to make every effort to recover the islands through diplomatic channels.”

The hardline position taken by Mr Milei is nonetheless less hostile than that of Alberto Fernandez, his Left-wing predecessor, who had called for immediate negotiations.

Mr Milei has insisted any transfer of power must be peaceful and has deemed it a lesser priority than the country’s return to economic growth.

The libertarian economist also argued on the election trail: “What we are proposing is to move towards a solution like the one England had with China over the Hong Kong issue and that, in this context, the position of the people who live on the islands cannot be ignored.”

In July, Rishi Sunak criticised the European Union for its “regrettable choice of words” after the bloc referred to the Falklands as Islas Malvinas, the name that Argentina claims is correct.

Mr Sunak’s spokesman said at the time: “Look, the Prime Minister’s view is that it would have been entirely unacceptable for the EU to question the Falkland islanders’ right to decide their own future. Let’s be clear – Falkland islanders are British.

“The EU has now rightly clarified that their position on the Falkland Islands has not changed after their regrettable choice of words. We will continue to defend the Falkland Islands’ right to determination.”