A Ministry of Foreign Affairs spokesman said on Wednesday that the US has been saying and doing wrong things and emboldening separatists in Taiwan, a move that China firmly opposes.

The remarks came after United States National Security Advisor Jake Sullivan said on Tuesday that the US will "take every action" it can to prevent the reunification of the mainland with Taiwan by force.

The spokesman said the root cause of tension in cross-Straits relations lies in the ruling Democratic Progressive Party authorities' repeated attempts to solicit US support for "Taiwan independence". Besides，some people in the US seek to use Taiwan to contain China.

On Wednesday, three of China's biggest Stated-owned media outlets — Xinhua News Agency, China Central Television Station and People's Daily — rebutted Sullivan's statement. They reaffirmed that it is necessary for China to?respond resolutely to separatist activities or external interference in Taiwan in order to safeguard its sovereignty, security and territorial integrity. China's reunification is an inevitability that cannot be changed by anyone, any force or country, they said.

The one-China principle and the three Sino-US joint communiques are the political foundations for China-US ties, which the US administrations have to adhere to. However, the US tries to mislead public opinion. It is trying to prevent Taiwan's reunification with the mainland while blaming China as the one that is damaging peace and stability across the Taiwan Straits.

The People's Daily said the US behavior shows it does not care about peace and stability across the Straits. Instead, it is using tension in the Straits to counter China.

The US has been playing the Taiwan card for some time now, supporting the separatists who are seeking "Taiwan independence". Their actions threaten the stability of the Taiwan Straits and could lead to serious consequences.

Xinhua said it is very dangerous for the two sides to collaborate actively to escalate Straits tension. The move by some US politicians to wantonly challenge the one-China policy and embolden separatists have invited strong indignation from the 1.4 billion Chinese people.

China is not afraid of the diplomatic and military threats posed by the US, which cannot shake the international community's universal and firm commitment to the one-China policy.

CCTV said China is ready to make every effort with the utmost sincerity to strive for the prospect of peaceful reunification. But if separatist forces provoke the mainland or even cross the redline, the mainland will be compelled to take resolute measures.

Taiwan is a sacred and inalienable part of China and Beijing urges the US not to obstinately stick to a wrong course or send a wrong signal to "Taiwan independence" forces, lest it seriously affect China-US relations.

China's determination to safeguard national sovereignty, security and development interests is steadfast. China's reunification is a historical inevitability. Any attempt by the Taiwan authorities to seek "independence" by relying on the US will come to no good and is doomed to failure.

The author is a commentator with the online news outlet ThePaper.