Manila, May 19 -- Oil companies announced big-time price increase in fuel prices starting May 20.

In separate advisories, Caltex, Cleanfuel, Jetti, Petro Gazz, Seaoil, and Shell said they will hike prices of gasoline by PHP1.20 per liter and diesel by PHP1.70 per liter.

Caltex, Seaoil, and Shell will also increase kerosene prices by PHP1.20 per liter.

Other oil firms are expected to follow suit.

For the past two weeks, oil firms implemented price rollbacks of PHP0.85 per liter for gasoline, PHP1.55 per liter for diesel, and PHP2.15 per liter for kerosene.

"Year-to-date, gasoline has a total net increase of PHP3.10 per liter as well as diesel with total net increase of PHP3 per liter. Kerosene has a total net decrease of PHP2 per lite...