Katrina Cooper to chair Thai-Cambodia UNCLOS commission

Australian diplomat and international lawyer Katrina Cooper has been appointed the fifth conciliator and chair of the Conciliation Commission handling the Thailand-Cambodia maritime-boundary process under the 1982 United Nations Convention on the Law of the Sea (UNCLOS).

Thailand’s Foreign Ministry said the Permanent Court of Arbitration (PCA) issued a statement on August 14 concerning Cooper’s appointment, and that Thailand had also received notification from the PCA.

Cooper was among the candidates supported by Thailand.

The ministry described her as an experienced diplomat and international lawyer with expertise in international law and negotiations, as well as experience dealing with sensitive issues in international relations.

Her appointment completes the five-member commission after Thailand and Cambodia each appointed two conciliators. The four members had been tasked with selecting a fifth person to serve as chair. The original deadline for doing so was July 19, but both countries agreed to extend it to August 14.

Thailand entered process in June

Cambodia transmitted its notification of conciliation to Thailand on June 2, and Thailand formally submitted its response on June 19, accepting participation in the proceedings while reaffirming that its objective was limited solely to maritime-boundary delimitation under UNCLOS.

Thailand appointed Deputy Prime Minister and Foreign Minister Sihasak Phuangketkeow as its Agent and Songchai Chaipatiyut, Thailand’s ambassador to Kuwait, as Deputy Agent.

It also named Judge Albert J. Hoffmann of South Africa and Judge Rüdiger Wolfrum of Germany as its two conciliators.

The Foreign Ministry has stressed that conciliation is not a court process.

The conciliators act as independent experts rather than legal representatives of either party and are tasked with hearing both sides and helping identify a balanced way forward.

The commission is expected to prepare a report containing recommendations in around 12 months unless the parties agree that more time is required.

The report will not be legally binding but may provide a basis for Thailand and Cambodia to continue negotiations towards a mutually acceptable settlement.

Cooper brings previous UNCLOS experience

The Foreign Ministry highlighted Cooper’s previous involvement in international diplomacy and maritime conciliation, including service as Australia’s ambassador to Mexico.

She also served as Australia’s Co-Agent in the UNCLOS conciliation between Australia and Timor-Leste. PCA records confirm that Cooper represented Australia as Co-Agent in that five-member conciliation process.

Her involvement in the Timor Sea proceedings gives her direct experience of the same type of UNCLOS conciliation mechanism now being used in the Thailand-Cambodia process.

First meeting expected in September

The next step is for the completed Conciliation Commission to set the date for its first meeting, which is preliminarily expected to take place in September 2026.

A key item on the agenda will be preparation of the Rules of Procedure, which will establish the framework governing the commission’s meetings and subsequent stages of the proceedings.

Thailand said it was ready to cooperate fully with and support the commission as a peaceful dispute-settlement mechanism under UNCLOS.

The Foreign Ministry and other relevant Thai agencies will continue participating on the basis of international law while seeking to protect Thailand’s national interests and work towards a sustainable resolution for both countries.