Argentina will present a formal complaint at the United Nations over Britain's "militarization" of the situation in the Falkland islands, President Cristina Kirchner said Tuesday.

"We will present a complaint to the UN Security Council and the UN General Assembly, as this militarization poses a grave danger to international security," Kirchner told a group of politicians and Falklands war veterans.

The two sides have ramped up the rhetoric in the run-up to the 30th anniversary of the war, which broke out on April 2, 1982, when the ruling junta in Buenos Aires invaded the disputed islands in a bid to end British rule.

Argentine officials have been seething in recent weeks, denouncing the deployment of a British warship and the dispatch of Prince William, second in line to the throne, for a tour of duty as a helicopter pilot.

Britain "is once again in the process of militarizing the south Atlantic," Kirchner said.

"We cannot interpret in any other way the deployment of an ultra-modern destroyer accompanying the heir to the throne, who we would prefer to see in civilian attire."

Hundreds of protesters rallied near the government palace where Kirchner was speaking, waving Argentine flags and shouting: "Malvinas! They belong to us!" referring to the islands as they are known here.

Britain has held the Falkland islands since 1833.