Defence Minister Prawit Wongsuwon on Wednesday ordered the navy to delay sending its submarine purchase proposal to cabinet for approval, amid concern about opposition to the project.
Gen Prawit said the plan to buy three submarines from China will not be on the cabinet's agenda until the Royal Thai Navy does a better job of raising awareness about why it needs them.
The navy should clearly explain to the people the benefits of having submarines to protect the national interest in territorial waters, he said.
The navy is pushing for the procurement of three fully-equipped Chinese submarines at 12 billion baht apiece, but the project still needs endorsement from the cabinet after being approved by the Defence Ministry.
The plan has received backing from Prime Minister Prayut Chan-o-ocha and from Gen Prawit, who is deputy prime minister in charge of security affairs.
But it also encountered fierce opposition, in particular criticism from the Pheu Thai Party and the People's Democratic Reform Committee, and social activists. They urged the government to use the money to help the country out of the economic slump and to recitify social problems, instead of buying new weapons.
The prime minister on Wednesday reiterated his support for the scheme, saying the navy had made a thorough study of the need to have submarines before it propose the procurement.
It had been planned to put the submarine project on the cabinet agenda on Tuesday.
But a high-ranking navy source close to the project said it was deferred over concerns about the level of criticism of Thailand and China about the handing over of 109 Uighur illegal migrants to Chinese authorities.
The navy and the ministry were worried that the anger of Thai activists and the public in some quarters about the Uighur issue could spill over and derail the procurement plan, because the submarines would be bought from China, the source said.