Britain would find it difficult to defend, reinforce or retake the Falkland Islands if Argentina launched a fresh assault, according to a defence pressure group.
The UK National Defence Association (UKNDA) said on Sunday that the islands are more vulnerable than at any time since the invasion in 1982.
Britain could not deploy sufficient forces in time to defend or reinforce the islands, the UKNDA claimed.
The report said: "Even in the most favourable circumstances... the deployment of additional fighters and a reasonable war-fighting force would take approximately a week.
"In effect, this means that the British garrison would necessarily have to hold Mount Pleasant airfield and its environs for a week before help arrived.
"There would be no fighter cover for the landing force and shipping. There is no carrier... There is no question of providing air support using RAF fighters.
"There are no bases within range. In-flight re-fuelling, given the number of re-fuels required for a round trip of 8,000 miles from Ascension, would be impossible in the face of the threat posed by the Argentine Air Force.
"The UK would be hard put to protect, reinforce or retake the islands... history could well be about to repeat itself - but this time with a different outcome."
The report was prepared with contributions from Falklands veterans Major-General Julian Thompson, of the Royal Marines, Captain Michael Clapp, of the Royal Navy, and Air Commodore Andrew Lambert, of the Royal Air Force.
They were assisted by military historian Andrew Roberts and by the UKNDA's chief executive, Commander John Muxworthy RN, and deputy chief executive Andy Smith.
On Friday, Daniel Filmus, a senior politician in Argentina's ruling party told Radio Five Live that the Falkland Islands will belong to Argentina one day.