Dear Dr. Owen.
Thank you for your letter of 17 April. I am surprised that you do not consider that the Foreign and Commonwealth Secretary gave you a response in the debate on 16 April to your questions about consultation with the United States concerning the targets of their recent military action in Libya. It is clear from the Official Report that he told the House that the conditions set for American targeting were both clear and explicit.
As I made clear to the House on 15 April, the Government agreed to the use of United States aircraft based in the United Kingdom, if that was necessary, in actions in self-defence against specific targets demonstrably involved in the conduct and support of terrorist activities. I reserved the position of the United Kingdom on any question of further action which might be more general or less clearly directed against terrorism. It is also clearly understood between President Reagan and myself that, if there were any question of using United States aircraft based in this country in a further action, that would be the subject of a new approach to the United Kingdom under the joint consultation arrangements. [end p1]
It is inherent in any arrangement providing for a joint decision before action can proceed that either party can withhold agreement until it is satisfied on any point. However, my exchanges with President Reagan prior to the United States military action on 14 April were confidential, and I am not prepared to go into detail.
I am aware of your position that dual-key arrangements should have been provided before ground-launched cruise missiles were introduced into the United Kingdom. You will also recall the reasons why the Government did not proceed with this option. It would have required United Kingdom ownership of the missiles, just as the Thor missiles to which you refer had been owned by the United Kingdom, at a cost of around £1 billion. The Government took the view that, since perfectly satisfactory arrangements existed to prevent any nuclear weapon being fired or launched from British territory without the agreement of the British Prime Minister, this expenditure could not be justified.
Far from casting doubt on the effectiveness of our consultation arrangements with the United States about the use of their bases in this country, the events of recent days have demonstrated that the United States fully observes those arrangements and that the agreements upon which we rely are a full safeguard. You yourself refer to the full involvement of the British Government in the consultative procedures which would be entailed in any North Atlantic Treaty Organisation decision affecting the use of American bases in this country.
Yours sincerely
Margaret Thatcher