Argentina's President Cristina Kirchner renewed her country's demand for sovereignty over the British-ruled Falkland Islands at the UN Security Council on Tuesday.
"This is not a fanciful stance. We simply want the United Nations resolution to be enforced and for our two countries to sit down and discuss this," she said.
Argentina is the new chair of the Security Council, and Kirchner admitted it was controversial to raise the Falklands during a debate ostensibly about the United Nations' ties with regional bodies.
Britain is a permanent member of the Security Council and its ambassador, Sir Mark Lyall Grant, was in the chamber to hear Kirchner's speech.
Kirchner recalled that the UN General Assembly passed a resolution in 1964 urging Britain and Argentina to hold negotiations over sovereign of the islands, which Britain has ruled since 1933.
Speaking the day after UN Secretary General Ban Ki-moon notified her that Britain had again refused to discuss the sovereignty issue, Kirchner questioned Britain's commitment to upholding UN resolutions.
"One can have discordant opinions about something that has not been resolved by the United Nations, but when this body that covers us all, that we are all signatories of, whose resolutions we have all committed to respect, issues a resolution through its General Assembly, this body's maximum organ, its not a matter of discordant opinions," she said.
"We are before a UN resolution, and are we ready to fulfill what we're obligated to do or not?" she said.
Argentina invaded the islands in April 1982, prompting Britain to send a task force of 100 ships to recapture them in a war in which 649 Argentine and 244 British troops died.
In March, Falkland Islanders voted 99.8 percent to remain a British territory. But Argentina rejected the vote as meaningless and Kirchner has repeatedly staked its claim.