The Royal Thai Navy (RTN) on May 8 signed a contract with a Chinese company to procure a S26T diesel-electric submarine. [Photo/en.people.cn]

The Royal Thai Navy (RTN) on Monday signed a contract with a Chinese company to procure a S26T diesel-electric submarine, a move experts believe will promote China's export of conventional submarines.

The contract was signed in Beijing by RTN chief of staff, Vice Admiral Luechai Ruddit and Xu Ziqiu, chairman of the stated-owned China Shipbuilding Industry Corporation (CSIC). According to CSIC's official website, this is the company's second submarine export contract, after an eight-ship deal with Pakistan's navy in 2015.

"The submarines from China are the cheapest, with quality that is relatively acceptable. [China] also offers services after purchase, something extra that we have received," Thailand's Prime Minister Prayut Chan-o-cha was quoted as saying by Nationmultimedia.com in March.

The S26T will be the RTN's first submarine since the end of World War II. Due to domestic politics and a budget shortage, the country delayed its plan to buy a submarine until China offered an unbeatable deal.

According to Nationmultimedia.com, the ship will be nearly 78 meters long and 9 meters wide. It will be equipped with the latest technology, including a AIP (Air Independent Propulsion) system, which will allow the ship to stay underwater for up to 21 days without resurfacing. Normal nuclear-based submarines can dive for around seven to 10 days at a time.