740.0011 Pacific War/674
The British Embassy to the Department of State 52
There are important indications that Japan is about to attack Thailand and that this attack will include a sea-borne expedition to seize strategic points in the Kra isthmus.
We have plans for the rapid movement of a force from Malaya to hold a line across the Kra isthmus in the neighbourhood of Singora. Time is the essence of this plan, particularly at this season of the year when the Kra isthmus is water logged. Consequently great tactical advantage lies with the side which gets there first.
R. A. F.53 are reconnoitering on arc of 180 miles from Tedta Bharu for three days commencing November 29th and our Commander in Chief, Far East has requested Commander in Chief, Asiatic Fleet at Manila to undertake air reconnaissance on line Manila–Camranh Bay on the same days. Commander in Chief, Far East, has asked for permission to move into Kra isthmus, if air reconnaissance establishes the fact that escorted Japanese ships are approaching the coast of Thailand, and he asks for an immediate decision on this point.
To allow the Japanese to establish themselves so near the Malay frontier would be an obvious threat to Singapore even though at the present season it might not develop at once. We have also to bear in mind the encouragement which the Japanese success would give to their extremists. Demands of appetite would grow and other Far East peoples would be correspondingly depressed. It looks therefore as though, to ensure the defense of Singapore and for wider reasons, we might have to take the proposed action to forestall the Japanese.