Motorists will face mixed pump price adjustments starting Tuesday morning, with diesel expected to become cheaper while gasoline and kerosene prices could either increase or decrease depending on each oil company's pricing.

The Department of Energy's (DOE) Oil Industry Management Bureau said gasoline prices may either decline by as much as P0.10 per liter or increase by up to P1.90 per liter.

Diesel prices are set to either roll back by as much as P1.16 per liter or increase by up to P0.84 per liter.

Kerosene prices, meanwhile, could either fall by P0.78 per liter or rise by as much as P1.22 per liter.

Energy Secretary Sharon S. Garin told reporters on Monday that the adjustments represent the allowable range of pump price movements based on prevailing trends in the international oil market.

She said the DOE shifted to a price range after global oil markets began to stabilize, replacing the earlier policy of prescribing a single price adjustment during the energy emergency.

"Before the energy emergency, DOE had more of a monitoring power on the price of oil. It means that the oil company decides how much the price will roll back or increase," Garin said.

"Now that we're in an emergency, and the system is broken, and prices suddenly rose, DOE decided that we will dictate what the rollback or the price increase will be."

Garin said the DOE computes the allowable range by averaging the costs incurred by oil companies, which differ depending on where they source their fuel, the size of their purchases, and their freight, insurance, and transportation expenses.

"Now, because the market is calming down, we put a price range so that it can get closer to what the actual expense of the companies is paying for the oil they're buying," she said.

"So, that's why there's a price range. It's not a choice, but each company can choose within the range of what they will mark up or mark down," Garin added.

As of 26 June, government data showed that the country had an average fuel inventory equivalent to 41.16 days of demand, indicating sufficient petroleum stocks to meet domestic requirements.

Gasoline inventories were enough for 42.19 days, while diesel stocks—the country's main transport and industrial fuel—were sufficient for 37.66 days. LPG inventories stood at 35.75 days, jet fuel at 70.83 days, kerosene at 212.41 days, and fuel oil at 27.87 days of supply.