Manila:Seven Indonesian sailors have been kidnapped and were probably being held in Sulu province of Philippines, a military spokesman said on Sunday. They were kidnapped "on the high seas of Indonesia around June 22", Xinhua news agency quoted Brigadier General Restituto Padilla as saying. He said the military "is now assessing the situation and will plan for the best course of action". No further details of the abductions were provided by Padilla. The abductions prompted Jakarta to halt its coal shipment to the Philippines unless the kidnapped sailors are secured. Indonesian Foreign Minister Retno Marsudi on Friday said: "The moratorium on coal exports to the Philippines will be extended until there is a guarantee for security from the Philippine government." Indonesia supplies 70 per cent of the Philippines' coal import needs. The notorious Abu Sayyaf group has not so far claimed responsibility for the latest hostage-taking. Last March and April, at least 14 Indonesian sailors were abducted in two separate incidents, according to the Philippine military. They were all freed in May. The Philippines, Indonesia and Malaysia have recently agreed to intensify their security operations in Sulu Sea where the Abu Sayyaf militants are operating. This month, the three agreed to designate a transit corridor for commercial vessels crossing their water borders.