In a follow-up to the growing hijacking problem in southern Philippines waters, the Indonesian government has asked Philippines authorities to help ensure the safety of Indonesian vessels in their jurisdiction, Coordinating Political, Legal and Security Minister Luhut Pandjaitan was quoted as saying by local media.

"There should be security personnel for all Indonesian barges that cross our territory into the Philippines, including during unloading and on the journey back to our country," Luhut said.

Following a spate of kidnappings of Indonesian sailors by the Abu Sayyaf militant group in the southern Philippines, Indonesian Transportation Minister Ignatius Jonan had previously asked the Philippine ambassador to ensure the security of Indonesian vessels in waters between the two countries, Luhut said.

Efforts to conduct joint sea patrols by Malaysia, the Philippines and Indonesia to maintain security in waters bordering the three countries have been slow in implementation as defense ministers have differences, Luhut said.

"Joint patrols are yet to be performed as there are differences between the officials and their counterparts in the Philippines," Luhut said, adding that Indonesia hoped the Philippines would give a favorable response to the matter.

The Philippines would appear to be worse affected, as almost all its coal comes from Indonesia and supplies have been hit by the Indonesian government's moratorium on coal exports to the country amid uncertain security.