China-Philippines relations took a fresh hit after Beijing warned Manila to stop “theatrics,” following a top government official’s sharp rebuke to China at a recent defense summit.

Philippine Defense Secretary Gilberto Teodoro Jr. read a note slipped to him from the Chinese side at the Seoul Defense Dialogue on Tuesday, stunning the audience, and adding a fresh irritant to China-Philippines relations already frayed over the South China Sea.

The message, handed to Teodoro mid-panel, laid out China’s position on the 2016 South China Sea arbitration ruling, restating Beijing’s rejection of the verdict that favored Manila.

Teodoro rebutted it on the spot, accusing Beijing of “coercion, bullying and aggression” in the South China Sea. The clip of his remarks went viral in the Philippines, while the reaction on Chinese social media was comparatively muted.

“It is one of the rarest occasions when the PRC government was openly rebutted in a public forum like this,” said Collin Koh, a senior fellow at the S. Rajaratnam School of International Studies. Koh described Teodoro’s action as consistent with Manila’s standing policy on the sea dispute, and his own “vocal, strident personality.”

Teodoro has been sanctioned by Beijing since June, barring him, his wife, and child from entering Chinese territory over what it called “erroneous remarks against China.”

Chinese foreign ministry spokesperson Mao Ning told reporters Wednesday she wasn’t aware of exactly what happened but stated that Beijing “urges the certain individual of the Philippine side to cut the provocations and theatrics, and stop undermining China-Philippines relations and stability in the South China Sea.”

Hu Xijin, who retired as editor-in-chief of state media Global Times and is now one of the country’s most influential commentators, wrote late Thursday that Teodoro’s actions were “an outright breach of diplomatic bottom line.”

China and the Philippines have been locked in dispute over their competing claims in the South China Sea for years, and friction has intensified in recent months. Chinese coast guard vessels firing water cannon at a Philippine ship near Scarborough Shoal in July, and Beijing’s declaration of a “nature reserve” around the shoal have also prompted protest from Manila.

Analysts see the verbal spat as another sign of tensions already running high, and likely to give Beijing an opening to ramp up nationalist rhetoric against Manila, short of any serious military escalation.

The episode will likely add to the tensions, Koh said, as Teodoro’s confrontation probably galvanized public support at home, while Beijing won’t back down either. But he doesn’t expect it to spiral into armed conflict.

Both governments desire stability in the relationship, particularly after President Ferdinand Marcos Jr. signaled willingness to “reset” ties with Beijing, Koh said. If anything, he expects Beijing to single out certain officials it views as “diehard anti-PRC,” like Teodoro, and set the narrative of distinguishing them from the rest of the country.

“The incident is a symptom of ongoing tensions rather than a cause of anything,” said Ja Ian Chong, an associate professor of political science at the National University of Singapore.

Manila would continue to hold its ground while leaving the door open to talks with Beijing, he said. Beijing, for its part, “has little incentive to change tack for now, given its superior capabilities,” Chong said, a dynamic that lets China absorb public embarrassments like the one in Seoul, without altering its broader strategy toward Manila.