Cambodia's Interior Ministry has released a directive instructing all government officials to encrypt their communications to "protect information related to national security."

The statement came in the wake of rising tension with Thailand over "stolen confidential documents" related to the arrest of Thai engineer Siwarak Chutipong, an employee of CATS, a subsidiary of Samart Group, on charge of being a "spy."

Interior Minister Sar Kheng said in the directive that newly encryption technology that will "guarantee secrecy" so that government information will not be leaked.

The directive was signed Oct 15. Interior Ministry spokesman Khieu Sopheak said such measures were necessary in Cambodia's present diplomatic circumstances, according to Phnom Penh Post.

"If Thaksin would have been arrested because of (Siwarak) leaking information about him, that would prove we could not keep sensitive information a secret," the spokesman said.

Siwarak's defence attorney, Kav Soupha, said that he did not believe that the leaking of Thaksin's flight schedule constituted a threat to Cambodia's national security.

"Thaksin is not the prime minister of Cambodia..he is a convicted man who is being hunted by Thai authorities. Even if (Siwarak) had reported to the Thai embassy, that would be according his right and obligation as a Thai citizen to alert authorities about a fugitive...." the attorney was quoted by PP Post as saying.