The government of the Falkland Islands said it was "satisfied" that defence cuts were not leaving it vulnerable to an invasion by Argentina.
A group of former Royal Navy chiefs cited the risk to the South Atlantic islands in a public call on the coalition not to scrap the aircraft carrier Ark Royal and the fleet of Harrier jets.
In a letter to the Times, the commanders said the move would leave the oil-rich territory open to a fresh Argentinian attack "from which British prestige...might never recover".
One, Lord West, said that if they were captured "we have absolutely no way whatsoever of recovering them unless we have got carrier air."
The fate of the islands has been a major issue in criticism of the cuts but their government said it had received assurances that the UK would maintain an effective deterrent.
"The Falkland Islands government is satisfied by, and grateful for, the level of defence on the islands which the British Government has assured us is suitable to maintain an effective deterrent," it said in a statement responding to the latest claims.
Buenos Aires has revived its demands for the islands it calls the Malvinas since oil firms began explorations for possible reserves in Falklands waters earlier this year.
The senior retired commanders, who also included former Admiral of the Fleet Sir Julian Oswald, Vice-Admiral Sir Jeremy Blackham, Vice-Admiral John McAnally and Major-General Julian Thompson, said the Harrier decision was "strategically and financially perverse".
"In respect of the newly valuable Falklands and their oilfields, because of these and other cuts, for the next 10 years at least, Argentina is practically invited to attempt to inflict on us a national humiliation on the scale of the loss of Singapore.
"One from which British prestige, let alone the administration in power at the time, might never recover," they wrote in the letter.
They invoked the threat of Nazi Germany the 1930s to reinforce their message: "The last Treasury-driven '10-year rule' in the 1930s nearly cost us our freedom, faced with Hitler."
And they concluded: "We believe that these decisions should be rescinded in the over-riding national interest, before it is too late."
Lord West, the former First Sea Lord who also served as a counter-terrorism minister in the previous Labour government, said Argentina still regarded sovereignty as a "major issue".
But the Falklands were just one example of the impact of lost capability, he warned.
"It applies all around the world. The only way to get fixed-wing air covering our troops is to have them on aircraft carriers," he told BBC Radio 4's Today programme.
"The Tornado can't get to any of these places."
The coalition Government announced a series of deep cuts in the armed forces as part of last month's Strategic Defence and Security Review.
Defence Secretary Liam Fox defended the changes.
He told The Times: "It is simply not the case that decommissioning the Harrier would impact upon our ability to defend territories in the South Atlantic.
"We maintain a wide range of assets, not least a well-defended airfield to ensure the defence of the Falkland Islands.
"The Harrier force has made an impressive contribution to our nation's security over the decades but difficult decisions had to be made... and I'm clear that rationalising our fast jet fleet makes both operational and economic common sense."Reuse content