“We have not had any underwater safeguard mechanism for a really long time,” Navy spokesperson Vice Admiral Jumpol Lumpikanon said. “The submarines’ mission is not only to defend and safeguard [security] but also to explore new things.”

The Navy has proposed to set aside Bt18 billion from the national budget to buy three Yuan Class S26 T submarines from China, but the proposal has been hanging fire for years. The Cabinet of the military-backed government of General Prayut Chan-o-cha, said it agreed with idea to have submarines but the approval to kick-start the deal has not yet proceeded.

While the Cabinet approved the Army proposal to buy 10 tanks from China on Tuesday, the Navy’s plan is still awaiting a final nod.

A proposal on the Navy’s budget, to be committed from this fiscal year until 2023, has been forwarded to the Defence Ministry to be sent to the Cabinet.

“It’s not my prerogative to speak of when the proposal will be looked at by the Cabinet,” Jumpol said. “The details of the procurement contract can only be revealed once the Cabinet gives the nod.”

The Kingdom has been without submarines since 1951, the year Thailand discharged four Japanese submarines from service.

Although the public has cast doubts over the necessity for such expensive hardware, the government believes the country is in dire need of these submarines because of increasing maritime threats elsewhere, Jumpon said.

For instance, he said, the South Korean Cheonan ship sank in 2010 but the causes remain unclear. In Sri Lanka, the now-defunct Liberation Tigers of Tamil Eelam also built their own submarines to attack coastal ships.

Assistant commander-in-chief Admiral Naris Pratoomsuwan said the Navy had reasons to protect the maritime interests of the country, which has a strategically favourable location with enormous economic and energy potential.

“Amid the growing influence of great powers, it is a challenge for Thailand to pursue its foreign policies,” Naris said. “And we know how to maximise maritime benefits,”

Commerce Deputy Minister Sonthirat Sonthijirawong also supported the deployment of submarines considering Thailand’s 3,000-kilometre-long coastline with maritime resources.

“Our sea regions are connected and open, making it easy for external intrusion,” Sonthirat said. “Without submarines, we could lose lots of economic opportunities. This submarine deal should also be regarded carefully from an economic perspective.”