Argentina’s President Cristina Fernandez de Kirchner has appeared before a UN committee, demanding Britain discuss her country’s claim to the Falklands Islands, on the 30th anniversary of the war over the disputed territory.Kirchner made a highly unusual appearance at the UN decolonisation committee on Thursday to challenge Britain, which has steadfastly refused contacts on sovereignty."We are not asking anyone to say yes, the Malvinas belong to Argentina,” Kirchner said, using the Spanish name for the British-ruled islands. "We are asking no more, no less than to sit down and talk.”Kirchner’s decision to speak to a committee that is typically the realm of mid-ranking diplomats is the latest move in her wide-ranging diplomatic offensive to assert her country’s claims to the islands, which the Argentine military invaded and occupied for 74 days in 1982.Tensions between Argentina and Britain have escalated in recent months, especially since British companies have started to carry out offshore oil exploration.Kirchner told the committee the fact that the Falklands remain under British rule and are not part of Argentina is "an affront to the world which we all dream of”."How can it be part of British territory when it’s 14,000 miles away?” she asked. In London, Britain’s Prime Minister David Cameron vowed to defend the Falklands against new "aggression” and said there could be no sovereignty negotiations."My message to the government of Argentina is this: the UK has no aggressive intentions towards you. Accusations of militarisation and nuclear threats are hyperbole and propaganda,” he said.Britain says it will agree to talks only if the 3,000 islanders want them.