170 Lord Cranborne, U.K. Secretary of State for Dominion Affairs, to Mr John Curtin, Prime Minister
Circular cablegram M438 LONDON, 7 December 1941, 5.06 a.m.
MOST IMMEDIATE MOST SECRET
Following for the Prime Minister.
My immediately preceding telegram M.437. 
1. Since the possibility remains open that the immediate
destination of the Japanese convoys is another port in Indo-China
there may still be time for warning to Japan by the United States,
Dutch and ourselves on the lines contemplated in recent exchanges
with President Roosevelt. We have therefore thought it desirable
to continue preparations for the delivery of such a warning in
order to be in a position to proceed with it if and when the
President should give the signal to do so.
2. We have not yet heard whether the President has decided to send
the message to the Emperor or not. If he has not yet made up his
mind the decision may now be influenced by the news of the sailing
of Japanese convoys. We must assume in any event that he may wish
to proceed with some form of warning at any moment in which case
warnings from ourselves and the Dutch may be required to follow
almost immediately afterwards.
3. It would we feel add to the impressiveness of warning (if the
President should wish us to proceed with it) if it could be
delivered on behalf of all His Majesty's Governments jointly. We
very much hope His Majesty's Governments in the Dominions will
feel able to concur in this course and identify themselves in this
manner with the warning proposed.
4. In view of the urgency of the matter as explained in paragraph
(2) we have thought it desirable to prepare and telegraph to His
Majesty's Ambassador at Tokyo  a draft note to the Japanese
Government conveying a warning in the sense agreed in the recent
discussions with the President. The text is contained in my
immediately following telegram  and it will be seen that in the
hope that the suggestions made in paragraph
(3) above will be acceptable it has been drafted as a joint
communication. Sir R. Craigie has been instructed to hold this
draft note in reserve pending receipt of further instructions and
it has been explained to him that the text as well as the form is
subject to the concurrence of His Majesty's Governments in the
Dominions. The draft has been telegraphed simultaneously to His
Majesty's Ambassador at Washington  for the observations of the
President. It has also been sent to the Netherlands Government
which is entirely in agreement with the line taken by us and is
preparing to act similarly.
5. We should be grateful if we could be informed by most immediate
telegram whether you concur in the terms of the draft note and in
the procedure suggested.  In the circumstances it would be
helpful if you would cause your reply to be repeated to His
Majesty's Ambassador at Tokyo. 
6. It will be appreciated that in drafting the note we were
presented with a special difficulty owing to the desire of the
President that the Burma Road should be omitted from the warning
(see my telegrams M.433 paragraph (2) and M.434 paragraph (1)).
In the circumstances we have thought it best to relate the warning
directly to the concentration of troops in southern Indo-China.
The draft note thus brushes aside the Japanese explanation about
north Indo-China and leads logically to the Japanese threat to
Thailand  as well of course as the Netherlands East Indies.
This has the merit of being in accordance with immediate realities
and the fact that the Philippines are also omitted (in accordance
paragraph (3) my telegram M.433) should, we feel, make the absence
of mention of the Burma Road less noticeable.
[AA: A981, JAPAN 18511, iii]