President of Argentina Javier Milei has reiterated the country’s claim on the Falkland Islands and said he would introduce sanctions on any oil companies working in the area.

He was speaking in a national address amid renewed tensions over the British overseas territory after US President Donald Trump hinted the US would not help the UK in a future conflict over the islands.

Mr Milei said: “I want to be quite clear with everybody.

“The Falklands are Argentinean. Historically and legally.

“There can be no argument. They are part of the Argentine territory.

“The islanders on their usurped territory do not have a legitimate right to self-determination and any argument on any such self-determination is invalid.”

He said the UK was facing “multiple crises on multiple fronts”, adding that he would sign decrees to introduce sanctions against any companies working on oil production in the area.

Mr Milei declared the Sea Lion oilfield, owned by an Israeli and a British firm where production is expected to begin in 2028, a “clear and present danger” to the country’s claims.

“If we do not act swiftly in a few months, they will have the material capacity to access the oil that lies underneath our sea,” he said.

“Something that has never happened before,” he added.

His address came as his approval ratings plummet, just over a year before he seeks re-election.

Polls show only around 34% of Argentines supporting his drastic belt-tightening and deregulation policies.

Announcing plans for a naval base in Tierre del Fuego in the south of Argentina, he said Mr Trump and the US was “assessing their historical position” in regard to the Falkland Islands.

Mr Trump’s announcement on Monday that the United States is reviewing its position on the Falkland Islands came amid reports Washington is threatening to oppose Britain’s sovereignty if it does not increase defence spending.

In an interview yesterday with the British network GB News, Mr Trump criticised the UK’s lack of military support for his war with Iran and refused to confirm whether he would back Britain in a potential new dispute with Argentina.

The last war in 1982 “was a long time ago”, he said.

“The Falklands issue serves Trump’s purpose of pressuring the United Kingdom to comply with his demands regarding NATO funding and cooperation in the war in Iran,” Tomas Mugica, director of the Center for International Studies at the Catholic University of Argentina, told AFP.

Mr Milei presented Washington’s review of its stance as a vindication of his policies and support for the Trump administration.

“The United States is considering this change of position because it knows that Argentina has a reliable partner,” he said.

Sarah Rogers, a senior official in the US State Department, wrote on X that “exciting things are happening in the Western Hemisphere” alongside a photo of her and Mr Milei ahead of his speech.

Although the US is formally neutral, Washington provided support for Britain’s campaign to retake the islands after the Argentinian invasion in 1982.

Earlier this year, Argentina players held up a banner saying “the Falklands are Argentine” after beating England 2-1 in the World Cup semi-final.

Argentines refer to the South Atlantic archipelago as Las Malvinas.

In a 2013 referendum, the Falkland Islanders voted overwhelmingly to remain a British overseas territory, with 99.8% voting in favour and just three votes against.

Downing Street said earlier this week that the UK’s position on the Falklands was “long-standing and unwavering”.

It said: “Sovereignty rests with the UK, and the islanders’ right to self-determination is paramount.

“The UK’s position is clear. The islanders have repeatedly expressed their wish to remain a British overseas territory.”

The Falklands War began when Argentine forces invaded the islands in April 1982, prompting then-British prime minister Margaret Thatcher to send a naval task force to reclaim them.

The war left 649 Argentines, 255 Britons and three islanders dead.

Additional reporting AFP