There have been times when the Chinese and Philippine governments have agreed their relationship is much bigger than their South China Sea disputes.

In those times, those disputes were managed relatively well, as were bilateral ties in general.

Yet those times seem to be over, at least under the current administration in Manila, and a regrettable lack of wise helmsmanship from it is sending the once manageable ties toward a dangerous fractiousness. To make things worse, third parties, in the region and beyond, are deliberately exacerbating the frictions.

As Chinese and Philippine government officials continue trading accusations over the World War II ship Manila grounded on China's Ren'ai Reef in 1999, the encounters between their maritime forces are grinding toward a spark. Manila has deployed several ships to "monitor" the supposed illegal activities of China, said the office of President Ferdinand Marcos Jr. Multiple vessels of the Chinese People's Liberation Army's Southern Theater Command Navy have been sent to the South China Sea for a "combat training exercise".

As both governments insist, neither side wants the altercation to spiral out of control. But as their latest dispute over the alleged telephone conversation between a Philippine admiral and a Chinese official indicates, the drain of mutual trust is amplifying mutual animosity. And those ill feelings are increasingly poisoned by outsider interference.

According to Chinese diplomatic sources, Chinese and Philippine officials had reached a "gentleman's agreement" on the latter's missions to supply its troops on the grounded warship with life necessities. Per the transcript of the phone conversation between Philippine Vice-Admiral Alberto Carlos and an unidentified Chinese official, they agreed to a "new model" for such missions. The "new model" limited resupplies to food, fresh water and other humanitarian materials on condition prior notice was given to the Chinese side. After violating it by sending building materials to the grounded vessel, Manila now flatly denies the existence of the agreement despite Philippine and Western media publishing a transcript of the conversation that makes clear the agreement was made.

First there was the Armed Forces of the Philippines chief of staff denying the authenticity of the transcript, claiming "it appears to be a malign influence effort" from Beijing. Then came the Philippine national security adviser, who accused the staff members in the Chinese embassy in Manila of violating their domestic law, and appealed for their expulsion.

Manila has clearly been emboldened by its closer association with regional and extra-regional powers, from the security partnership it just formulated with the United States and Japan to the recent US decision to deploy medium-range missiles on Philippine soil. But for all its willingness to make peace, Beijing cannot afford to budge on a matter of national sovereignty and territorial integrity.

Beijing and Manila once demonstrated they could make peace on their own. Sadly the latter seems more than ready to consign its own future to outsiders preoccupied with strategic rivalry with China, whatever the cost.