Thatcher pleaded for Irish help during Falklands war

Mrs Thatcher admitted she had been forced to turn to “close friends” for support because she suspected the Soviet Union would block any United Nations (UN) proposed sanctions.

“I now seek your personal help to bring about the urgent introduction of economic and financial measures against Argentina, by national action co-ordinated among us,” she wrote to Mr Haughey.

In the message, marked “personal and confidential”, the Tory leader said Argentina had made clear it would defy a UN Security Council resolution issued on April 3, 1982 to withdraw its forces from the Falkland Islands.

Calling for all available means to be brought to bear on the invading troops, Mrs Thatcher said economic and financial measures would have a particularly powerful impact.

The Argentinian economy was fragile and vulnerable and “measures to limit their access to markets and to credit will hit them hard”.

Britain’s actions would be “far more effective if our close friends and trading partners will support us as fully as possible”, she added.

Thatcher said time was short and experience had shown – in the case of Iran two years earlier – that the Soviet Union would veto UN proposals for a global economic assault on Argentina.

“I must therefore turn to you, together with our other friends, to ask you to take national action in solidarity with us in introducing economic measures,” she wrote to Mr Haughey.

The British leader openly accepted that sanctions would hit the Irish economy as much as the Argentinians.

“I know that these measures will affect your own economic interests,” she said in the message, released into the National Archives in Dublin from the taoiseach’s department.

But she insisted they would bring the Argentinian government “to their senses” and quickly lead to a peaceful withdrawal of troops from the disputed territory off Argentina in the south Atlantic.

As well as a complete ban on the supply of arms, an embargo on all or some imports from Argentina, Mrs Thatcher sought an Irish ban on export credit guarantees and international lending to the south American country.

Predicting that international money markets would cease loans to Argentina because of the economic upset, she appealed to Mr Haughey: “I ask you to provide no incentive and no encouragement.”

The Department of Foreign Affairs said Ireland did not directly impose any financial or trading sanctions on Argentina during the war.

“The only measures taken by Ireland in the course of the hostilities between the UK and Argentina were those taken by us as a member state of the then EEC, e.g. the EEC arms embargo of 1982,” a spokeswoman said.

The State papers show Mrs Thatcher made similar pleas to the United States, Japan, Canada, Australia and New Zealand.