245 Lord Cranborne, U.K. Secretary of State for Dominion Affairs, to Sir Geoffrey Whiskard, U.K. High Commissioner in Australia
Cablegram 4 LONDON, 3 January 1941, 11.30 p.m.
MOST SECRET AND PERSONAL
My telegram of 11th December, Circular Z.407. 
Please give the following information, which is of the highest degree of secrecy, to the Prime Minister  for his most secret and personal information. BEGINS.
1. Staff conversations with officers of the Netherlands East Indies took place at Singapore 26th-28th November.
2. Dutch expressed themselves as ready to co-operate with us in joint plan to meet the contingency of war with Japan on the understanding that this does not imply any political commitment on either side. Plans were made with particular reference to a Japanese attack on Malaya, Borneo or the Netherlands East Indies, which would appear to be among their most probable courses of action.
3. Dutch representatives were in agreement with our views regarding the role of their forces in the event of war as stated in paragraph 37 of summary of Chiefs of Staff, Far East, appreciation contained in my telegram of 12th August, Z.214 , and in paragraph 1 (j) of my telegram of 16th October, Z.308. 
4. It was agreed that the only practicable form of co-operation by re-distribution of forces must in present circumstances be limited to air forces. No mutual re-distribution was recommended regarding naval and land forces presumably owing to the necessity of retaining limited forces available for local defence of Dutch territory. In the event of attack on Borneo Dutch might move certain bomber squadrons there, in which event the R.A.F. might take over air operations south of Singapore and west of Borneo operating from aerodromes in Sumatra and West Borneo. In the event of attack on Malaya Dutch squadrons which could be spared from local defence might operate in Malaya. British squadrons might operate from Dutch bases in Northern Sumatra in these circumstances. Each command would retain power to recall any reinforcements lent in this manner.
5. Arrangements for command envisaged in paragraph 4 of my telegram Z.308 were agreed. Areas of responsibility for reconnaissance were also agreed.
6. It was recommended that liaison officers (one from each service) should be exchanged as soon as possible between ourselves and the Netherlands East Indies. This matter is being taken up with the Netherlands Government in London and we are despatching suitable officers to take up duties as soon as the necessary formalities are completed.
7. Preparation and issue of inter-allied code was recommended.
Improved naval code for inter-communication between British and Netherlands naval authorities in the Far East is now under preparation. Separate War Office code will not be required. Air Ministry are considering advisability of preparing code for air forces.
8. Conference also recommended that facilities should be provided (including provision of bombs, preferably spares, fuel etc.) to enable R.A.F. and R.A.A.F. aircraft to operate from certain Dutch aerodromes and Dutch aircraft to operate from certain British aerodromes in Malay Peninsula and Borneo. Agreement of Netherlands Government to provision of these mutual facilities is being sought here. Netherlands East Indies representatives stated that they could provide adequate landing grounds and refuelling stations between Timor Sea and Malaya. They added that ample releases of suitable aviation fuel can be made available at all operational aerodromes and seaplane bases in the Netherlands East Indies.
9. It was also proposed that an attempt should be made to define what action by Japanese forces should be regarded as an act of war. This has been considered here but it is felt that action by Japan which would constitute an act of war could only be decided by H.M. Governments in the light of circumstances at the time and that planning should be conducted on the assumption that war might break out as a result of some hostile act by Japan, the precise form of which cannot at present be foreseen.
10. Conference reported that duration of Dutch resistance to Japanese would be limited by their existing shortage of armaments and munitions and recommend that everything possible should be done to secure delivery of material already ordered for the Netherlands East Indies from the United States of America and the British Empire. This recommendation is accepted and steps are being taken to investigate means whereby this may be accomplished.
11. Netherlands East Indies representatives asked for information regarding arrangements for controlling Japanese at Tawao Si Amil (north of Tarakan) and Malaya. This matter is under urgent consideration here.
12. Netherlands East Indies representatives also asked if we could influence the Portuguese Government with a view to preventing further concessions to the Japanese in Portuguese Timor. This proposal is being taken up with the Portuguese Government.
13. In the course of the conversations the following information was also elicited:-
(a) Denial of Dutch oilfields. As regards plans for demolition of Dutch oilfields see my telegram of 14th December, Z.411. 
(b) Dutch air reconnaissance. Regular flights of mails made over northern approaches to Netherlands East Indies, the west coast of Sumatra and Sunda Straits.
(c) Dutch Air Force dispositions. General intention of Netherlands East Indies authorities is to re-distribute squadrons as necessary to meet any threat that may develop. They intend stationing some flying units in East Borneo to protect Tarakan and Balikpapan oilfields.
14. Full information regarding defence and resources of the Netherlands East Indies was also given by the Netherlands East Indies representatives. This included plan for employment of Dutch naval forces, facilities for laying minefields.
15. Netherlands East Indies representatives asked for information regarding control in the event of war of Torres Straits, and were informed that this question was under active consideration by the Commonwealth authorities.
16. The fact that these conversations have taken place should be regarded as most secret and on no account be divulged even to representatives of the Netherlands East Indies in the Commonwealth or New Zealand. ENDS.