China's foreign ministry said it would respond to any move that undermines core interests, after the US foreign minister said Taiwan "is not part of China".
During a press conference on November 13, Chinese Foreign Ministry spokesman Uong Van Ban said Taiwan is part of China's territory and cannot be violated.
Mr. Uong Van Ban accused US Secretary of State Mike Pompeo of causing further harm to the Sino-US relationship.
"We solemnly tell Mr. Pompeo and people like him that any act that undermines China's core interests and interferes in China's domestic affairs will be responded by China. determined ", Mr. Uong said.
China views Taiwan as a separatist province and will unify at all costs, including force. They also consider this as the most sensitive and important issue in relations with the US. Beijing has been angry many times over the Trump administration's increased support for the island, such as arms sales.
"Taiwan is not part of China," Pompeo said in an interview on a US radio station on November 12.
Officially, since 1979, the US has acknowledged China's stance that Taiwan is part of it, according to the "One China" principle. However, over the years, Washington has become the most powerful supporter of Taiwan in the international arena.
China has imposed sanctions on US companies that sell weapons to Taiwan. The People's Liberation Army has also stepped up fighter jets closer to the island, including the visits of high-ranking US officials to Taipei this year.