Philippine Defence Secretary Gilberto Teodoro said on Friday that China's rules about how its Coast Guard can operate in the South China Sea were a matter of international concern, describing them as a provocation.

China, which has maritime sovereignty disputes with the Philippines and other claimant countries in the South China Sea, has issued new rules that would enforce a 2021 law explicitly allowing its Coast Guard to fire on foreign vessels.

“Such behaviour is not only a violation of UNCLOS, but also a violation of precepts the UN charter which lays upon each responsible state the duty to refrain from the use of force or aggression to enforce, particularly in this case, illegal territorial claims in the maritime domain,” Teodoro said in a speech at the Philippine Navy's anniversary.

“That is a provocation insofar as I am concerned,” he added.

The Philippines and China have had several maritime run-ins in the South China Sea in the past few months that included the use of water cannon by Chinese coast guard vessels that damaged Manila's boats and injured crew members.

Responding to concerns, the Chinese foreign ministry has said this week the new rules were meant to protect the maritime order, and that there was no need to worry if there was no illegal behaviour by the individuals and bodies involved.