The Philippines government says is prepared to go to war if China unilaterally mines the natural resources of the South China Sea.
The Asian country had raised concerns over the continued military build-up by China in the disputed areas declared by a UN arbitration court to belong to Manila, its capital.
President Rodrigo Duterte has faced criticisms for not confronting Beijing following news that China had installed missile systems on artificial islands in the busy waterway.
Duterte, unlike his predecessor, is said to enjoy good relations with Beijing and wants its investment, reportedly saying he cannot afford to go to war with a far superior China.
But Alan Cayetano, foreign minister, has defended the Philippines government from allegations that it is taking a soft policy on Chinese militarisation of the South China Sea.
“President (Rodrigo Duterte) has already said that If anyone gets the natural resources in the Western Philippines Sea, South China Sea, he will go to war,” Cayetano said.
“We are taking all diplomatic actions at the right time,” adding that “China had been told of the red lines”.
Hermogenes Esperon, national security adviser, said the Philippines would always try to pursue talks to defuse tension, but war could not be ruled out as a last resort if its military is provoked or aggrieved.
“The other night, the president said if his troops are harmed, that could be his red line,” Esperon said.
China claims most of the South China Sea, through which about $3 trillion worth of goods passes every year.
It has made substantial progress in fortifying its manmade islands in the past few years, which it says it has the right to defend.
On May 17, the Philippines expressed “serious concern” over the presence of China’s strategic bombers in the disputed waters, but its response to the installation of missile systems was muted.