Prime Minister Paetongtarn Shinawatra said there is no doubt about Koh Kut's status as a Thai sovereign territory, amid growing concern over the island's inclusion in a 2001 memorandum of understanding (MoU) with Cambodia about the management of resources in the overlapping claims area.
While there is no question about the island's status, the PM admitted that the controversial MoU cannot be unilaterally revoked without Cambodia's agreement.
Her assurance echoed Interior Minister Anutin Charnvirakul's recent remark over the island's status.
"As the interior minister, I confirm that Koh Kut undoubtedly and completely belongs to Thailand. Fellow Thais live there, and it is recognised as a district of Trat," Mr Anutin said, noting various legal documents and royal commands that reflect the general acceptance of the idea that the island belongs to Thailand.
The 2001 MoU between Thailand and Cambodia grabbed public attention after observers pointed out that if the document is used as the basis for negotiations on the management of marine resources in the overlapping claims area, then the Thai government risks losing sovereignty over Koh Kut.
Defence Minister Phumtham Wechayachai dismissed the concern on Monday, saying the MoU is meant to facilitate the management of marine resources in the Gulf of Thailand and has nothing to do with Koh Kut.
He said that the MoU was not revoked when the Abhisit Vejjajiva administration took power, and any future talks on joint marine interests between Cambodia and Thailand will have to cover the demarcation of the maritime border between the two countries.
Sontirat Sontijirawong, head of academic and policy affairs of the Palang Pracharath Party (PPRP), said the Abhisit administration -- which includes leaders and members of parties in the current government coalition -- had agreed in principle to revoke the MoU on Nov 10, 2009.
"These parties include [what is now] Bhumjaithai," Mr Sontirat said, in an apparent reference to Mr Anutin, the current leader of the Bhumjaithai Party.
"I would like current coalition parties to confirm their intention to cancel the 2001 MoU to protect the nation's interests," said Mr Sontirat, who is a former energy and commerce minister.
Suriyasai Katasila, a former coordinator of People's Alliance for Democracy or the yellow shirts, said there are attempts to discredit critics of the 2001 MoU as nationalists.
He argued that such attempts will only further polarise the nation and won't benefit the country.
Mr Suriyasai noted that critics' focus is not on Koh Kut, but the claims about overlapping areas made by Cambodia for the negotiations with Thailand over joint maritime resource sharing.