1\. The Japanese Government will be aware that under the London Naval Treaty of 1936 and the corresponding bi-lateral agreements with Germany and Soviet Russia His Majesty's Government in the United Kingdom is precluded from constructing capital ships (i. e. vessels of more than 10,000 tons standard displacement or with a gun of more than 8 inches) which exceed 35,000 tons or carry a gun of more than 16 inches or which are less than 17,500 tons or carry a gun less than 10 inches. As regards cruisers (i.e. vessels of not more than 10,000 tons with a gun of not more than 8 inches) His Majesty's Government is limited to a maximum of 8,000 tons with 6 inch guns.
2\. The Japanese Government has unfortunately not seen its way to subscribing to the London Naval Treaty nor has it hitherto felt able to give any assurances that Treaty limits would in practice be adhered to by it.
3\. As the Japanese Government will be aware the Naval Treaties give His Majesty's Government a right of escalation in the event of building not in conformity with Treaty limits by a Power not a
party thereto. There have for some time been persistent and cumulative reports which, in the absence of explicit assurances from the Japanese Government that they are ill founded, must be deemed to be authentic, that Japan has undertaken or intends to undertake construction of capital ships and cruisers not in conformity with the above-mentioned limits. His Majesty's Government has therefore decided that it will be necessary for it to exercise its right of escalation unless the Japanese Government can furnish the aforesaid assurances and can satisfy His Majesty's Government that it will not, prior to 1st January 1943, lay down, complete or acquire any vessel which does not conform to the limits in question without previously informing His Majesty's Government of its intention to do so and of the tonnage and the calibre of the largest gun of the vessel or vessels concerned.
4\. In view of the forthcoming publication of naval estimates and the necessity for giving other Treaty Powers information as to intended British construction His Majesty's Government will be glad to receive a reply not later than February 20th next. Should no reply be received by that date or should the reply be lacking in the desired information and assurances, it will be compelled to assume that the Japanese Government either is constructing or acquiring or has authorized the construction or acquisition of vessels not in conformity with the limits referred to. His Majesty's Government would thereupon be obliged, in consultation with other naval Powers with whom it is in treaty relations, to resume full liberty of action. If, however, the Japanese Government, though engaged in or intending to engage in construction not in conformity with the treaty limits, were willing to indicate forthwith tonnages and calibres of guns of vessels which it was constructing, or was intending to construct, His Majesty's Government for its part would be ready to discuss with the Japanese Government the question of the tonnages and gun calibres to be adhered to in the future if the Japanese Government were now prepared to agree to some limitation. It would, however, be necessary that such consultation should be completed by April 1st.