Philippine President Rodrigo Duterte has threatened to deploy military forces to the South China Sea to stop China from claiming natural resources in the contested waters.

Duterte made the remark in a televised address , while noting that a conflict with China would not end “without any bloodshed” and Manila might not be able to win such a confrontation.

“If we go there to assert our jurisdiction, it will be bloody,” Duterte said. However, he claimed that “there is no other way but a war” to enforce a 2016 Hague tribunal ruling that confirmed the Philippines’ sovereign rights in its exclusive economic zone.

“We can retake it only by force. There is no way we can get back what they call the Philippine Sea without any bloodshed,” he said.

The Philippine president further said he was “not so much interested” in confronting China over fishing rights in the disputed waterway.

“I’m not so much interested now in fishing. I don’t think there’s enough fish to quarrel about,” Duterte said.

“But when we start to mine, when we start to get whatever it is in the bowels of the China Sea, our oil, by that time, I will send my grey ships there to stake a claim,” he said, referring to Philippine naval ships.

“If they start drilling oil there, I will tell China, is that part of our agreement? If that is not part of our agreement, I will also drill oil there,” he said. “If they get the oil, that would be the time that we should act on it.”

The remarks came after hundreds of Chinese vessels were spotted at the Julina Felipe Reef, a disputed coral reef that is miles west of the archipelagic province of Palawan, as well as other parts of the West Philippine Sea.

Meanwhile, Philippine Defense Chief Delfin Lorenzana said naval ships can patrol the country’s exclusive economic zone, after the president said that “nothing will happen” if the nation sends its ships “because we are not in the possession of the sea.”

The latest development comes at a time of heightened tensions over the disputed South China Sea islands between the two countries in the past weeks. The Philippines has repeatedly protested China’s presence and has deployed more vessels in disputed areas.