Timor Sea Office
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In the lead-up to Timor-Leste's restoration of independence on 20 May 2002, the Timor Sea Office, then part of the United Nations Transitional Administration in East Timor (UNTAET), negotiated the Timor Sea Treaty. This agreement with Australia establishes a temporary petroleum revenue sharing area in the Timor Sea.

Since that time, the Timor Sea Office worked to obtain the ratification of the Timor Sea Treaty by the Timor-Leste Parliament (achieved in December 2002) and negotiated the International Unitisation Agreement and Memorandum of Understanding for the Greater Sunrise gas field with Australia (signed in March 2003).

On the commercial side, the Timor Sea Office negotiated the production sharing contract and development plan approval for the gas phase of the Bayu-Undan development (located in the Timor Sea Treaty area) with petroleum company ConocoPhillips, and worked to obtain passage by the Timor-Leste Parliament of tax legislation for the Bayu-Undan development (all completed in June 2003).

The Timor Sea Office formulates and implements the Timor-Leste Government's public information campaign on the Timor Sea. The purpose of the campaign is to inform both the Timorese people and interested persons abroad about issues relating to the Timor Sea, and the oil and gas resources that lie beneath it.

At present, the primary task of the Timor Sea Office is the establishment of permanent maritime boundaries with Australia and Indonesia.

Brief History of the Timor Sea

Following the unlawful Indonesian invasion of Timor-Leste in 1975 and Australia's de jure recognition of Indonesian sovereignty in Timor-Leste in 1979, Indonesia and Australia sought to agree to a permanent maritime boundary in the Timor Sea that would resolve the problem of the "Timor Gap."

The Gap was left by the 1972 seabed boundary agreement between Australian and Indonesia, and was a legacy of the fact that Australia and Portugal - the colonial ruler of Timor-Leste at that time - had been unable to agree to a maritime boundary between Portuguese Timor and Australia. Moreover, Portugal never recognised the validity of the endpoints of the 1972 Indonesia-Australia agreement. See Map.

In its negotiations with Indonesia, Australia hoped to close the Gap by connecting the two end points of the 1972 agreement. Indonesia, however, was unwilling to agree to a maritime boundary for Timor-Leste that was based on recognition of Australia's outdated "continental shelf" argument, as the 1972 agreement had been.

Ultimately, Australia and Indonesia arrived at the solution of reaching a temporary agreement to develop jointly the petroleum resources of the Timor Sea, in the absence of permanent boundaries. In 1989, Indonesia and Australia signed the Timor Gap Treaty. Under the Timor Gap Treaty, petroleum revenues in Zone A were shared 50-50 between Indonesia and Australia, revenues in Zone B were shared 90-10 in favour of Australia and revenues in Zone C were shared 90-10 in favour of Indonesia. See Map.

In 1999, the people of Timor-Leste voted overwhelmingly for independence from Indonesia. In doing so, they inherited the unresolved issue of ownership of the resources of the Timor Sea. In 2000, the United National Transitional Administration in East Timor (UNTAET), together with the East Timor Transitional Administration (ETTA), declared the 1989 Australia-Indonesia Timor Gap Treaty to be illegal. This declaration was made on the grounds that Indonesia, the illegal occupier of Timor-Leste, had no authority to make agreements on behalf of the people of Timor-Leste.

At the same time, UNTAET and Timor-Leste leaders sought to agree to a permanent maritime boundary in the Timor Sea with Australia. As Australia expressed an unwillingness to do so, the two sides ultimately agreed to create a new revenue sharing area in the Timor Sea. In the interest of expediency and in order to avoid a legal vacuum for existing Timor Sea investors, UNTAET and Timor-Leste leaders agreed to a new treaty encompassing an area equivalent to Zone A of the illegal Timor Gap Treaty. On 20 May 2002, the date of the restoration of Timor-Leste's independence, Timor-Leste and Australia signed the Timor Sea Treaty, which provides for the sharing of revenues 90-10 in Timor-Leste's favour.

In the absence of permanent maritime boundaries, however, the problem of the "Timor Gap" lives on. It is for this reason that the agreement of permanent maritime boundaries with Australia, and also with Indonesia, is an urgent priority of the Timor-Leste Government.

The history of the Timor Sea has been the subject of many journal articles and other publications. 'The Timor Gap, Wonosobo and the Fate of Portuguese Timor', by Robert J King, and 'Spatial Allocation of Continental Shelf Rights in the Timor Sea: Reflections on Maritime Delimitation and Joint Development', by Nuno Sergio Marques Antunes, are two particularly insightful accounts.

The Timor Sea Office - Who we are

Manuel de Lemos
Assistant Coordinator and Financial Manager

Paul Cleary
Communications Director

Manuel Mendonca
Assistant Communications Officer

Shane Matthews
Finance and Administration Manager

Marcos dos Santos
Accounts and Administration Officer

Rosita Noronha
Office Assistant

International experts

Peter W. Galbraith - head negotiator

A former US Ambassador to Croatia and Balkans peace negotiator, Galbraith was Director for Political, Constitutional and Electoral Affairs for UNTAET and Cabinet Member for Political Affairs and Timor Sea in the first East Timor Transitional Government. Galbraith led the successful negotiations for the Timor Sea Treaty.

Nuno Antunes - maritime law adviser

A commander and navigation specialist in the Portuguese Navy, Antunes holds a Phd in international law with a thesis on maritime boundary delimitation. He is a member of the International Law Association's 'Committee on Legal Issues of the Outer Continental Shelf'. He has published extensively on maritime boundary delimitation, including a highly recommended journal article on the Timor Sea available on this website.

Philip Daniel - petroleum fiscal adviser

Daniel is an economist with more than 20 years’ experience in advising and negotiating on behalf of developing countries for petroleum projects in many parts of the world. He is a member of the IMF international panel of fiscal experts. He first came to Timor-Leste in the IMF petroleum tax policy mission in 2000. Supported by the Asian Development Bank, Daniel worked on the closing stages of the Timor Sea Treaty negotiations, and then led the Timor-Leste negotiating team for agreements relating to the Bayu-Undan development and the Greater Sunrise Unitisation Agreement. He is a member of Timor-Leste’s maritime boundary negotiating team while also advising the Timor-Leste Government on fiscal aspects of oil and gas developments in the Timor Sea.




Paul Cleary
Communications Director


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