The Foreign Ministry has also not written to the Cambodian authorities regarding the matter, he said.

Don added that a number of casinos had opened in border areas without posing any problems.

The issue follows an allegation by anti-corruption activist Veera Somkwamkid, who claimed on his Facebook posts that the new casino was located in an adjoining border area and may be sited in Ta Phraya National Park, which forms part of a World Heritage Site.

Veera questioned why the military government had allowed this to happen, and suspected that the previous post that he made on the same issue had led to a warrant being issued for his arrest over a week ago for violation of the Computer Crime Act.

The casino is reported to be situated close to the Sai Takoo border checkpoint in Buri Ram province, in which former politician Newin Chidchob, who is now a football-club sponsor, is known to be influential.

Newin filed a complaint to the police seeking that Veera be charged for posts that he claimed had also implicated him of involvement with the casino, Nation TV reported.

In his latest post on Sunday, Veera did not mention Newin, but referred to some close aides to Cambodian leaders.

He also alleged that Thailand’s National Parks Department had being negligent in carrying out its duty.

This resulted in the agency undertaking an examination of the official map of the national park to prove that the casino was not located within its perimeter, followed by a prompt denial of Veera’s allegation.