China on Friday voiced strong protest against the illegal entry of a U.S. navy warship into the South China Sea, urging the U.S. to stop such acts of provocation. 

"On November 26, the U.S. navy entered China's territorial waters off the Xisha Islands without the permission of the Chinese government," said Geng Shuang, a spokesperson of the Chinese Foreign Ministry, adding that "such moves, a violation of both Chinese law and relevant international law, severely undermined China's sovereignty and put in jeopardy the peace, security and sound order in relevant waters." 

Chinese warships and military aircraft were immediately sent to identify the U.S. warship, warn and expel it, Geng said. 

China resolutely opposes such actions and had made a solemn representation to the U.S. and "we urge the U.S. side to immediately stop such provocation that infringes upon China's sovereignty and threatens China's security," he added.