1976 government papers
By Dominic Casciani
British officials predicted in 1976 that Argentina would invade the Falkland Islands, according to official documents.
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Papers placed in the National Archives reveal that Prime Minister Harold Wilson was warned that a conflict might be inevitable.
He was urged to restart talks with Buenos Aires to reach a deal over the South Atlantic islands.
Argentina invaded in 1982 - leading to a war that cost more than 900 lives.
In the Cabinet papers, seen for the first time, officials warn Harold Wilson that negotiations had to be restarted with Argentina - not least because the UK had few international friends over the historic dispute.
The islands are a British dependent territory, but Argentina maintains a claim to their sovereignty.
In one briefing document, the then Cabinet Secretary Sir John Hunt told the prime minister that time was ebbing away.
Disputed since 1800s
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"The foreign secretary's [Jim Callaghan] conclusion is that we must yield some ground and that our best source is to be prepared to discuss a lease-back arrangement with the Argentines," wrote Sir John.
"He argues that Argentina is now on a 'collision course' with us and cannot afford to back down; that there are many ways in which Argentina could act against us, including invasion of the islands... and that we are not in a position to reinforce and defend the islands as a long-term commitment.
"The alternative of standing firm and taking the consequences is accordingly not practicable."
Sir John said diplomats believed the momentum over the dispute could not be reversed and the prime minister had to take quick decisions. A military plan to retake the islands would have to be on a "major scale".
The government was debating launching a strategy aimed at locking Argentina into a long-term settlement.
The UK would share oil and fishing wealth from the area in return for postponing sovereignty talks.
Officials hoped this tactic could wrong-foot hardliners in Argentina and also provide breathing space for public opinion on all sides to soften enough to make a lease-back deal possible.
The Franks Report into the eventual war noted that as tension mounted during 1977, the government covertly sent a small naval force to the islands - but did not repeat the move when relations worsened again in 1981-2.
This has led some critics to blame prime minister Margaret Thatcher for the war, saying the decision to plan the withdrawal of the only naval vessel in the area sent the wrong signal to the military junta in Buenos Aires.
However, this same debate over military resources dogged the 1976 Labour government, show the papers.
In one document, the MoD says it would need a 5,000-strong garrison on the Falklands to defend its 1,800 inhabitants.
In another, the Foreign Office complains it does not want to spend £2m extending Port Stanley's runway.
"We would risk justifiable criticism, if anything went wrong, that we had failed to apply a proper judgement to the spending of public money," says the official.