Vice Foreign Minister Zhang Yesui summoned U.S. Ambassador to China Max Baucus on Oct 27, lodging “serious representations” and expressing “strong discontent” over a U.S. warship patrol in waters near China’s Nansha Islands in the South China Sea.

“This action by the United States threatens China’s sovereignty and security interests and endangers the safety of personnel and facilities on the reef, which is a serious provocation,” Zhang said.

Earlier on Oct 27, USS Lassen entered waters near Zhubi Reef without the permission of the Chinese government.

Zhang noted that it had done so regardless of China’s earlier dissuasion. China is “strongly discontented with and firmly against” the move, he said.

The vice foreign minister reiterated China’s claim of sovereignty over the Nansha Islands and its adjacent waters, on the basis that China discovered, named and developed them.

“The Chinese government will resolutely safeguard territorial sovereignty and legal sea interests, and China will do whatever necessary to oppose deliberate provocation from any country,” he warned.

Denying that China’s activity in the South China Sea will restrict freedom of navigation and overflight in accordance with international law, Zhang said China will nevertheless oppose any country infringing upon its sovereignty and security in the name of the freedom.

“There has been and will be no obstruction to navigation and overflight freedom in the South China Sea,” he said, labeling the US move “a show of force that is very likely to trigger an accident, threatening the rights of navigation and overflight shared by all countries, and harming peace and stability in the South China Sea.”

The United States should remember its commitment that it would take no position on territorial disputes, Zhang added.

On the evening of Oct 27, China’s Ministry of National Defense also criticized the USS Lassen’s foray as likely to “seriously harm mutual trust” between the two armed forces.