Foreign Relations of the United States Diplomatic Papers, 1941, The Far East, Volume V

751G.92/494

The British Embassy to the Department of State

Aidé-Mémoire

His Majesty’s Government in the United Kingdom are grateful for the indication of the views of the United States Government on the situation in Thailand and Indo-China which was conveyed to Mr. Butler⁶ by Mr. Sumner Welles⁷ in his interview on December 23rd,⁸ and are anxious to consult the United States Government as a matter of urgency on the conclusions which they have reached on the subject.

2. In the first place, His Majesty’s Government wish to inform the United States Government in the strictest confidence that the Governor-General of Indo-China⁹ sent his Aide-de-Camp, Capitaine Jouan, on a visit to Singapore from December 25th–31st, as a result of which the basis of an informal modus vivendi on economic matters was worked out; His Majesty’s Government hope in the course of future negotiations to achieve such a modus vivendi, aiming at the resumption of trade and shipping relations on a surer basis and the limitation in some measure of the volume of commodities from Indo-China reaching Japan and through Japan, Germany.

3. His Majesty’s Government welcomed this approach and the indications given by Capitaine Jouan of a desire on the part of Indo-China not only to co-operate with them but to resist further Japanese encroachments. In the course of the conversations at Singapore Capitaine Jouan made the following statements in regard to Thai[land].

4. In September the Thais demanded two unimportant small areas west of the Mekong River, in return for which the French asked for assurances that this was the final demand. The Thais would not guarantee this. In consequence the French refused any concessions and the Thais eventually declined to ratify the non-aggression pact. In November the Thais made sporadic attacks on French territory to which the French subsequently replied, though so far the Thai attacks had been ineffective in spite of published claims. Only 4 French had been killed in twenty raids. The Thais had suggested negotiations but no progress had yet been made. The French were unwilling now even to cede the original Thai demands, though they would accept an adjustment by a frontier commission and agree to handing over one or two small islands in the River. Japan had offered to mediate, but the French considered this far too dangerous. Capitaine Jouan stated however that they would welcome mediation by the United States, or alternatively by the United States and Great Britain jointly. The French had direct evidence that the Japanese had been supplying Thailand with aircraft and ammunition, and they believed that the Japanese were giving the Thais full information about French defences in spite of the Japanese claim to strict neutrality in the dispute.

5. Meanwhile His Majesty’s Minister at Bangkok has received information, which has not yet been fully confirmed, that Germany is sympathetic to the Thai claims in the Mekong area and that the French representative at Bangkok has been authorised by Vichy to negotiate. On the other hand the Thai Prime Minister has made the important statement that Thailand would be content at the present time if the French gave back the territory on the right bank of the Mekong and would accept the middle of the River as the frontier.

6. The attitude of His Majesty’s Government is governed by two major considerations:—

(a) that the dispute should be resolved peacefully and without delay, and

(b) that this result should not be achieved through the mediation of the Japanese, with or without the aid of the Germans.

His Majesty’s Government are principally anxious that neither party to the dispute should be under any obligation to Japan, and that the settlement of the dispute should strengthen the French in their resistance to Japanese pretensions. It therefore appears important to His Majesty’s Government that the dispute should be settled either by direct negotiations or with the aid of the United States and Great Britain.

7. If this is to be achieved it is obvious that mutual concessions will have to be made by both parties going somewhat beyond what either has hitherto been ready to make. In general terms these appear to involve:—

(a) the French being willing to concede the two strips of territory originally claimed by the Thais, plus at least some of the islands in the River, and

(b) the Thais being content with something less than their maximum requirements and being prepared to give adequate guarantees that no further demands will be made.

8. His Majesty’s Government have noted Mr. Welles’s view that any cessions of territory made by the French to the Thais in present circumstances would be virtually concessions to blackmail with possible repercussions elsewhere. His Majesty’s Government recognise the seriousness of this argument, and if the French were unwilling to consider a composition of the dispute involving any territorial changes whatsoever, His Majesty’s Government would themselves not wish to offer their mediation. This, however, does not appear to be the case and the United States Government may be willing to examine the situation in the light of Capitaine Jouan’s statement that the French authorities would welcome their mediation, and of the following considerations.

9. The longer the dispute continues the more both parties (and not only Thailand) lay themselves open to Japanese penetration or attack. Indeed Japan’s object in supplying Thailand with arms is doubtless to prolong the dispute and thus weaken both sides although a successful mediation would equally achieve for Japan important advantages in both countries. The strategic position which Japan no doubt hopes to acquire in both countries is one from which she can menace the integrity of other territories lying to the south.

10. To sum up, to allow the struggle to continue or to be settled by the Japanese is to strengthen the Japanese in South-East Asia to the detriment of Indo-China, Thailand, the Netherlands East Indies and the British possessions in the Far East, not to mention Great Britain and ultimately the United States themselves.

His Majesty’s Government would welcome an early expression of the views of the United States Government on the above. They feel that if anything is to be achieved by way of mediation it must be attempted with all possible speed, also that to propose open mediation by the United States and themselves would be unlikely to succeed, since it would immediately provoke counter-action by the Japanese and the Germans. They consider that the negotiations would ostensibly have to be undertaken directly between the two parties, British and American influence being exercised in the background.

Washington , January 6, 1941.

6. Nevile M. Butler, British Chargé in the United States.
7. Under Secretary of State.
8. See memorandum of December 23, 1940, Foreign Relations, 1940, vol. iv, p. 245.
9. Vice Adm. Jean Decoux.