The Port of Rotterdam has warned it may be carrying out surprise checks of bunker suppliers’ compliance with its licence requirements.

The port authority, along with its counterpart at Antwerp-Bruges, is making the use of mass flow meters mandatory in bunker supply operations from the start of next year.

“A valid bunkering licence remains mandatory for delivering these fuels,” the Port of Rotterdam said in a LinkedIn post on Thursday.

“Compliance with specific regulations is required and regularly monitored by port authorities, sometimes unannounced or triggered by market signals.”

MFMs installed on bunker barges by suppliers must be certified and registered with the port’s harbour master before January 1, 2026, the port authority said.