MANILA - International Criminal Court (ICC) Judge Raul Pangalangan said China will now find it hard to sign agreements to explore or exploit resources within disputed areas in the South China Sea following a United Nations-backed tribunal's unanimous decision on the Philippines' arbitration case against the Asian giant.

Speaking at the UP Forum on the West Philippine Sea on Friday, Pangalangan stressed that while a world power may decide to ignore a ruling by an international court, it cannot coerce other nations or parties that are legally bound to honor the decision to do otherwise.

"I doubt if China can sign an oil exploration agreement with any company which is either based or whose capital is based in a state which is a member-state of the UNCLOS (United Nations Convention on the Law of the Sea (UNCLOS)," he said.

In issuing a "unanimous award" to the Philippines earlier this week, the Permanent Court of Arbitration (PCA) based in The Hague ruled that none of the disputed Spratly Islands is capable of generating maritime zones; thus, some areas there are within the Exclusive Economic Zone (EEZ) of the Philippines.

The arbitral tribunal said China has violated the sovereign rights of the Philippines within its EEZ by conducting reclamation works in the Spratlys archipelago and interfering with Philippine fishing and oil explorations in the area.

''Having found that none of the features claimed by China was capable of generating an exclusive economic zone, the Tribunal found that it could - without delimiting a boundary - declare that certain sea areas are within the exclusive economic zone of the Philippines, because those areas are not overlapped by any possible entitlement of China," the tribunal said in its decision.

READ: China vows 'decisive response' to sea provocations

According to Pangalangan, a former UP law dean, all states that signed the UNCLOS as well as the Vienna Convention on the Laws of Treaties, which he described as a "legal regime," will be bound to respect the decision of the tribunal on the Philippines' arbitration case against China.

Both the Philippines and China are signatories to the UNCLOS.

"Every state that has signed that convention will be bound to respect the verdict of this tribunal," he said. "And we can invoke this decision in every member state of the UNCLOS where violations of the treaty are committed."

ENVIRONMENTAL PROTECTION

He added there is also "a whole network of treaty obligations for the protection of the environment" where the Philippines can use the PCA's decision to invoke violations of obligation by China.

In its ruling, the PCA said China "had caused severe harm to the coral reef environment and violated its obligation to preserve and protect fragile ecosystems and the habitat of depleted, threatened, or endangered species" with its large-scale land reclamation and construction of artificial islands at seven features in the Spratly Islands.

"The Tribunal also found that Chinese authorities were aware that Chinese fishermen have harvested endangered sea turtles, coral, and giant clams on a substantial scale in the South China Sea (using methods that inflict severe damage on the coral reef environment) and had not fulfilled their obligations to stop such activities," the arbitration court added.

'WE HAVE TO DARE'

Pangalangan, meanwhile, lauded former Foreign Affairs Secretary Albert del Rosario for "taking a risk" in filing the arbitration case even with critics saying that there was no certainty that Manila would secure a victory.

READ: Del Rosario: PH win shows 'right is might'

China boycotted the case, saying the arbitral tribunal had no jurisdiction, but the PCA actually "went out of its way to entertain points and arguments and even evidence from the Chinese side," said Pangalanan.

China was also furnished copies of all submissions, orders and rulings, and got "a fair hearing," he added.

"Well, today we have won, and I think it is a reminder to us that sometimes we have to dare, to venture beyond the comfort zone, so to speak, and look at international relations, international law as a different ballgame," Pangalanan said.

"A ballgame where principles do matter, a game that is structured in such a way that states are forced to look at their long-term interest in the upholding of certain principles, of certain values, and not just their short-term interest in specific outcomes, in short-term specific consequences."