Phuket Provincial Energy Officer Rattakorn Klinchan said the reduction, approved by the Fuel Fund Management Committee (FFMC), has lowered the retail price of standard diesel (B7) on the island to B40.69 per litre at service stations.
The price of B20 diesel has also been reduced, now standing at B33.20 per litre. However, prices for gasoline and gasohol products remain unchanged.
Fuel price data recorded in Phuket on Friday shows Gasohol 91 averaging B42.57 per litre, while Gasohol 95 ranged from B42.94 to B43.59 depending on the operator. Gasohol E20 was priced between B35.94 and B36.50 per litre, and gasoline stood at around B52.53 per litre.
Premium fuels continue to vary by provider, with premium diesel priced between B54.89 and B62.63 per litre, while Euro 5 premium diesel was reported at B56.09 per litre.
Mr Rattakorn said the reduction follows a resolution by the Energy Policy Administration Committee (EPAC) to cut the refinery price of diesel by B5 per litre from April 24 to May 9, and by B3 per litre from May 10 to May 19.
The measure is intended to help mitigate the impact of fluctuating global energy prices and reduce the cost burden on the public, he added.