Reference your telegram 162. [1]

Circular Z.66 [2] was despatched subsequent to discussions with
the Foreign Office at which I had urged the importance of a joint
declaration and drawing up some line beyond which Japan should not
go. Foreign Office rapprochement is necessary in the first place
to determine the limits of our vital interests before approaching
the United States. This is, I think, reasonable. Have submitted
that this is a matter for the Chiefs of Staff
You will recall that Dominions Office telegram 180 [3] stated that
the step which should constitute an act of war by Japan could only
be decided by the Governments in the light of circumstances at the
time.

I have included this item in comprehensive memorandum on the Far
East strategy [4] already submitted for examination by the Chiefs
of Staff and discussion by the Defence Committee, which Churchill
has agreed to convene specially for this purpose.

Will advise you further.

MENZIES