ARGENTINA has given a warning of “a drastic change” in its quest for sovereignty over the Falklands. It has also accused Britain of bad faith for failing to enter substantive talks on the future of the islands over which the two countries went to war 24 years ago.

The Government of Nestor Kirchner has indicated that it will take a hardline approach on issues such as fishing and oil exploration rights in pressing Argentina’s claim to the South Atlantic islands — a move that marks a significant deterioration in relations with Britain.

More than a thousand people died in the conflict that followed Argentina’s invasion of the islands in 1982. Margaret Thatcher sent a naval taskforce to the South Atlantic and the three-month conflict ended with Argentina’s surrender on June 14. Yesterday Britain announced plans for a “major celebration” to mark the 25th anniversary of the liberation next year. That is likely to include a service of remembrance at the islands’ capital, Port Stanley.

Argentina’s tougher approach to the sovereignty issue will cast doubts on moves to improve relations between Buenos Aires and Port Stanley. Argentina, which has blocked attempts to set up extra charter flights to the islands, is likely also to restrict co-operation on fishing and oil exploration.

Señor Kirchner, who is expected to win re-election next year, has told ministers that he will abandon the so-called “sovereignty umbrella” agreed by former President Menem, under which Argentina agreed to set aside claims over the Falklands to facilitate accords on fishing, oil exploration and transport. Señor Menem and Guido Di Tella, his Foreign Minister, had sought to eradicate the legacy of Argentina’s military dictatorship and the invasion to gain the goodwill of the islanders.

But Buenos Aires has grown impatient with London’s refusal to enter negotiations over sovereignty, believing that Britain has abused its position to exploit fishing rights at the expense of Argentine trawlers.

Of particular concern to the Argentinians was the extension of British-issued fishing licences, some of which will be valid for up to 25 years after they are renewed next month.

Now Argentina is preparing to embark on a public relations offensive to win support for its claim to the islands it knows as Las Malvinas. On Thursday Señor Kirchner will launch a parliamentary commission on the Falklands, to comprise politicians and academics. The commission, which enjoys crossparty support, will be charged with developing the sovereignty claim and promoting the cause abroad.

Diplomats have been instructed to make the Falklands a priority, helping to keep the claim prominent on international agendas. They will present foreign counterparts with a DVD setting out the claim and Britain’s “non-fulfilment” of agreements established at the end of the conflict. But last night the Foreign and Commonwealth Office said that Britain’s position towards the disputed islands would not be swayed by the initiative.

“The UK will not negotiate on sovereignty unless and until the islanders wish it,” a spokesman said. “We remain committed to co-operation work on a bilateral agenda to the benefit of all, including Argentina.”

Last month Howard Pearce, the Governor of the Falklands, said that those living on the islands were still committed to remaining part of the UK. In his annual address he said: “Pressure (from Argentina) will prove utterly counter-productive. Falkland islanders are united in their wish to remain British.”

But the Argentine Government rejects the claim that the islanders have a right to self-determination. Jorge Taiana, the Foreign Minister, contends that they had been “planted” on what he called “sovereign Argentine territory”.

Earlier this month Señor Taiana spoke before the UN’s Decolonisation Committee, pushing for the ratification of a resolution calling for sovereignty negotiations to be resumed.

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