David Cameron today accused Argentina of "colonialism" as he insisted that Britain will continue to defend the right to self-determination of the people of the Falkland Islands for as long as they want it to.
Mr Cameron was speaking a day after a meeting of the National Security Council which discussed the situation in the South Atlantic as the 30th anniversary of the 1982 conflict with Argentina approaches.
The Prime Minister said he wanted to send a "strong message" about the islands which the Argentinians refer to as the Malvinas, following months of escalating rhetoric from Buenos Aires.
Speaking at Prime Minister's Questions in the Commons, Mr Cameron vowed to protect the islands' population and allow them to decide their own future.
"What the Argentinians have been saying recently, I would argue, is far more like colonialism because these people want to remain British and the Argentinians want them to do something else," he said.
Mr Cameron told MPs he ordered yesterday's NSC discussion so he could "make sure our defences and everything else is in order".
And he added: "It's very important we commemorate the Falklands War in this year, the 30th anniversary, and we remember all those who served and who fought so hard and those who gave their lives and didn't come home.
"The absolutely vital point is that we are clear that the future of the Falkland Islands is a matter for the people themselves.
"As long as they want to remain part of the United Kingdom and be British, they should be able to do so."
Mr Cameron repeated his message later in 10 Downing Street, at a press conference following talks with Italian MP Mario Monti.
"It is important for Britain to send a clear message that as long as people in the Falklands want to remain British, we respect that right of self-determination," said Mr Cameron.
"The reason for holding a National Security Council - which discussed other things as well - is to discuss that issue, is to make sure nobody is in any doubt that Britain supports that right of self-determination, and we will go on doing so for as long as people in the Falklands want to continue in that way.
"I think it is important that everyone understands that."
Tory MP Andrew Rosindell (Romford) branded Argentina's actions "wholly deplorable" and urged Mr Cameron to "remind Argentina they lost the Falklands War and that it's up to the Falklanders to determine their own future".
Speaking later, a source close to the PM said: "There has been quite a lot of rhetoric going on from Argentina and the Prime Minister is keen to show how important the protection of the Falklanders and their self-determination is to him."
The source said yesterday's NSC meeting sent "a strong signal" to the Argentinians.
On December 21 last year, the Mercosur grouping of countries, which includes Argentina, Uruguay, Brazil and Paraguay, announced that it would ban ships sailing under the Falkland Islands flag from docking at their ports.
But earlier this month, HMS Protector, the Royal Navy's ice patrol vessel currently on a scientific mission to the South Atlantic, called at Montevideo, Uruguay, en route to the Falklands.
Foreign Secretary William Hague is understood to be raising the Falklands issue during his current visit to Brazil.