He said that the security issues in the region were driving away potential investors that could exploit the hydrocarbon reserves of Liguasan Marsh, a 288,000-hectare area located in Cotabato, Maguindanao and Sultan Kudarat provinces.

"If peace and order in the area remain uncertain it will be difficult for the government to seek investors," Roxas told reporters.

The Philippine National Oil Company Exploration Corporation's (PNOC EC) is understood to be keen to expedite drilling operations in Liguasan Marsh after finding traces of oil and gas in Lambayong, Sultan Kudarat.