The Southern Theater Command of the People's Liberation Army conducted routine patrols in the South China Sea from Friday to Saturday, a spokesperson said on Sunday morning.

In a statement, Tian Junli, spokesman of the Southern Theater Command, noted that the Philippines has been frequently courting countries outside the region to organize so-called "joint patrols", spreading illegal claims about the South China Sea and undermining regional peace and stability.

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"We sternly warn the Philippines to immediately stop stirring up trouble in the South China Sea, escalating tensions," he said, stressing that bringing in external forces for support is destined to be futile.

The theater command's forces remain on high alert, resolutely safeguarding national sovereignty and security, as well as peace and stability in the South China Sea region, Tian said, warning that any attempt to create disturbances and disruptions will not succeed.