The government in July ordered all fishing vessels to register as part of a response to an EU warning over illegal fishing.

The European Union in January threatened an import ban on Thai fisheries products unless the country did more to crack down on illegal fishing practices including ocean bottom trawling and the use of push nets.

Those practices were already banned under Thai fishing regulations, but implementation was lax, and to be improved by the new registration scheme.

The ship owners affected by Tuesday’s move have “no channel to recover their licences and their vessels will remain in harbour” for the time being, Navy spokesperson Benjamaporn Wongnakornsawangthat said.

“Over 42 000 other vessels have registered and they will be allowed to continue fishing.”

The banned vessels range in size from small two-man fishing boats to 600-ton commercial ships.