The ship sank to a depth of about 50 metres and recovering it could cause damage that will make it more difficult to determine why it sank, the admiral said.
The navy is carefully selecting qualified contractors to salvage the vessel, Choengchai added.
The corvette-class ship sank about 20 nautical miles (32 kilometres) off the coast of Prachuap Khiri Khan’s Bang Saphan district on December 18 in stormy weather with 105 crew onboard.
Seventy-six members of the crew were rescued, the bodies of 24 were found recovered, and five remain missing.
Two million baht has been paid in compensation so far to the families of the deceased from the ship’s group life insurance policy and the navy’s Ruam Jai Fund, Choengchai said.
The navy is waiting for the court to declare the five missing crew members as missing persons to start paying the compensation to their families, he added.
Choengchai said the committee investigating the cause of the accident had finished interviewing 289 witnesses – surviving crew members, ship mechanics, and volunteers who participated in the search and rescue mission.
The navy is reviewing the witness statements and will determine the reason why the vessel sank after it examines the salvaged ship, he added.
An initial investigation by the navy’s Quartermaster Department found that the Sukhothai had 130 life jackets on board before it sank, which was a sufficient number for its 105 crew, Choengchai said.
The navy is also investigating why some crew members found, both alive and dead, were not wearing life jackets, he added.