Tom Allard recently reported in the Sydney Morning Herald that Australia and East Timor are ready to restart talks on the maritime boundary between the two countries, with all its complications of petroleum revenues and history. The tradition is to keep these talks under wraps, but Allard's article puts the topic back on the public stage. 

The Timor Sea and maritime arrangements between Australia and Timor Leste. (DFAT.)

If this issue were to be decided on the basis of 'they are poor and we are rich', then the facts are irrelevant, except perhaps for this fact: thanks to the existing treaty arrangements, Timor has a petroleum fund currently holding US$16.6 billion, unable to be effectively spent as fast as the revenue is flowing in

If poverty is not the criterion, then geography is. The original 1972 maritime boundary with Indonesia (West Timor and the parts of Indonesia to the east of East Timor) was drawn much closer to Indonesia than the mid-point between the two countries (see map above). This might seem unfair until you look at a cross-section map of the seabed or a map showing sea-depth (see map below), on which Australia's continental shelf is clear, as is the Timor Trench dividing the two land-masses.

The treaty history is summarised here. Portugal was still in control of East Timor at the time of the 1972 treaty, and it didn't want to participate in defining the border, hence the 'Timor Gap'. After Indonesia took over East Timor in 1975, this gap was addressed in a treaty which left the border to be determined later, but created the Joint Petroleum Development Area (JPDA; see first map) so that, in the meantime, the just-discovered petroleum resources could be developed.

After East Timor's independence from Indonesia, these delineations were retained in the new treaties, but a much more favourable division of the petroleum revenues was agreed. The Sunrise gas field (the richest undeveloped field, with estimates putting its gross value at $40 billion) lies mostly outside the JPDA, with about 20% in the Area and 80% in Australia's territory. The initial treaty with Indonesia had split the revenue within the JPDA 50:50, with Indonesia getting no share of gas field revenues outside of it. After the renegotiations, the newly independent East Timor received 90% of the JPDA revenue and 50% of the upstream revenues from the Australian part of Sunrise.

Sunrise gas field (Hydrocarbons Technology Market & Customer Insight)

A key element of all the treaties was to delay any consideration of the final border delineation of the Timor Gap for 50 years. If no development agreement was reached for the JPDA during the six years after the 2006 treaty was signed, either party could terminate it, but so far the treaty remains in force. Terminating it would open up the possibility of looking at the border again. But it would also affect the status of the revenues which both parties get from current production and might halt further investment. 

What would happen in a renegotiation? Allard asserts: 'A boundary equidistant between the two countries — as is the norm under international law — would result in most of the oil and gas reserves, worth more than $40 billion, lying within East Timor's territory.'

Yes, if the border were drawn equidistant, this would put the JPDA resources in Timor's territory, but Dili already gets 90% of these revenues. and it's true that UNCLOS decisions have favoured equidistant borders because continental shelf features are often unclear and subject to huge dispute.But in this case the shelf and the trench are indisputable geographic features. That said, Australia is not ready to have this tested and in 2002 declared that it would not submit itself to international dispute resolution mechanisms relating to 'sea boundary delimitations as well as those involving historic bays or titles.'

Even if East Timor were to succeed in renegotiating the border to mid-way (which, to give some idea how this would look, is the south-eastern edge of the JPDA shown on the first map), this still wouldn't put the rich prize of Sunrise in Timor's territory. Most of Sunrise is clearly to the east of the nearly north-south line demarking the eastern edge of the JPDA. This border is not in dispute and it is drawn in accordance with the conventional rules based on the geography of East Timor and Indonesia.

Going one step further, if East Timor succeeded in getting an equidistant border, Indonesia would surely want to do the same thing and could find an excuse. This would put the largest part of Sunrise in Indonesian territory. East Timor might then see if Indonesia was ready to share the revenues 50:50 with it.

Australia's negotiating history on this subject is not a glorious one. Why, for instance, was it worth the risk of getting caught spying on East Timorese negotiators when, as the Foreign Minister of the time said, 'you didn't have to spy on the East Timorese to find out what their position was'. Defending the current arrangements shouldn't be too hard, either on legal or moral grounds. Let's hope we make a better fist of it this time.