OIL firms cut pump prices of diesel by 25 centavos per liter effective Tuesday. Pilipinas Shell Petroleum Corp. (PSPC), Seaoil Philippines Inc. (SPI) and Petron Corp. effected the price cut starting at 12:01 am Tuesday while Phoenix Petroleum Corp. and PTT Philippines at 6 am the same day. The firms said the price changes reflected international market prices.Oil firms did not announce price cut on gasoline and kerosene. The Department of Energy’s (DOE’s) oil monitor reported that diesel prices per liter played between P28.85-32.20 as of June 16, with most retail stations offering at P30.05. The report was released after the price increase last week.