100 Mr A. Eden, U.K. Secretary of State for Dominion Affairs, to Mr R. G. Menzies, Prime Minister
Circular cablegram D84 LONDON, 14 March 1940, 2.42 p.m.
MOST SECRET AND PERSONAL
My telegram 12th January, Circular D. 18. 
Following for the Prime Minister:-
We have been considering further in the light of the replies received to Circular D. 18 the question of issuing a joint Anglo- French declaration engaging not to conclude a separate peace. It is dear from replies received from His Majesty's Government in Canada and in the Union of South Africa that they would regard their participation in such a declaration as impracticable at the present time, and in the circumstances, any such declaration would have to be limited to the United Kingdom and France. On the other hand, if a declaration in the name of the United Kingdom and France alone were issued it seems to us that there might be some risk that this fact would provoke speculation and enquiry as to His Majesty's Governments in the Dominions and so afford material for enemy propaganda.
We have consulted His Majesty's Ambassador in Paris  who has expressed himself as strongly in favour of a declaration from the point of view of Anglo-French relations. He considers that it would impose a solemn and binding obligation upon all future French Governments who, whatever their political complex, would find it virtually impossible publicly to repudiate an engagement of this kind. Moreover, if made at an early date, he feels that the declaration would weaken the position of such elements in France as may be working to undermine the pacific factor with a view to forming a Government more inclined to seek an early peace with Germany.
He has suggested however that the proposed text of the declaration might be expanded so as to give some contractual volition to the continuance of Anglo-French economic and military collaboration after the end of the war, and he feels that in addition to the good effect of such a further declaration upon the outside world, it would be of immense encouragement to the French and would assist Anglo-French relations when the time came to arrange terms of peace.
It occurs to us also that to link up the declaration with the Anglo-French financial agreement of 4th December last  and economic arrangements now in force between the two countries to which the Dominions are not parties might afford a reasonable ground which could be used in publicity to explain the non- participation of His Majesty's Government[s] in the Dominions in the declaration.
We are considering, therefore, the issue of a declaration on the lines set out in paragraph 2 of Circular D. 18, with the addition of the following sentence:-
'The two Governments further declare their intention to continue the closest co-operation in their financial, economic and defence policies after the conclusion of peace'.
On examining the draft declaration it has also occurred to us that the strength of the declaration would be improved by the addition, after the words 'French Republic' of the following:-'being equally determined to carry the war with the utmost vigour until the purposes for which it was undertaken are obtained'.
Before these suggestions are discussed further with the French Government, we should be glad to be in possession of the views of His Majesty's Governments in the Dominions. An early reply would be appreciated in view of the desire of the French Government for an early decision regarding the declaration.