MANILA -- Mercury Drug said Monday it was working with suppliers to replenish its stock of face masks after demand from those seeking to protect themselves from Taal Volcano ash fall depleted inventory.

Areas affected by the volcanic eruption will be prioritized when distributing face mask supply, the country's largest drug store chain said.

Mercury Drug said face mask prices would remain steady and it would not hoard supply.

Vice Mayor Honey Lacuna-Pangan earlier said she received reports that face masks had sold for P200 from P25 to P30 apiece before the eruption.