Five Power Defence Arrangements

The Five Power Defence Arrangements (FPDA) are a series of defence relationships established by a series of multi-lateral agreements between the United Kingdom, Australia, New Zealand, Malaysia and Singapore (all Commonwealth members) signed in 1971, whereby the five powers are to consult each other "immediately" in the event or threat of an armed attack on Malaysia or Singapore for the purpose of deciding what measures should be taken jointly or separately in response. There is no specific commitment to intervene militarily. The Five Powers Defence Arrangements do not refer to exclusive economic zones (EEZ) and the enforcement of a state's EEZ rights is a matter for that state; a state may request the assistance of other states in so doing.

The FPDA was set up following the termination of the United Kingdom's defence guarantees of Malaysia and Singapore under the Anglo-Malayan Defence Agreement, as a result of the UK's decision in 1967 to withdraw its armed forces east of Suez. Under the Five Powers Defence Arrangements, the five powers (Australia, New Zealand, Malaysia, Singapore and the UK) are to consult each other "immediately" in the event or threat of an armed attack on Malaysia or Singapore for the purpose of deciding what measures should be taken jointly or separately in response. There is no specific commitment to intervene militarily." The FPDA provides defence co-operation between the countries, establishing an Integrated Air Defence System (IADS) for Peninsular Malaysia and Singapore based at RMAF Butterworth under the command of an Australian Air Vice-Marshal (2-star). RMAF Butterworth, was under the control of the Royal Australian Air Force until 1988, and is now run by the Royal Malaysian Air Force but hosts rotating detachments of aircraft and personnel from all five countries.

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