TAIPEI (Taiwan News) — The Ministry of Foreign Affairs on Sunday condemned a letter written by China’s permanent UN representative Fu Cong to UN Secretary-General Antonio Guterres asserting sovereignty over Taiwan.

The letter, sent on Friday, criticized Japanese Prime Minister Takaichi Sanae for saying that a Chinese invasion of Taiwan could prompt a military response from Tokyo, according to China’s State Council. Fu called Takaichi’s comments “provocative” and “gravely erroneous and extremely dangerous.”

“Taiwan is China’s sacred territory, and how to resolve the Taiwan question is a matter for the Chinese people and brooks no foreign interference,” Fu wrote.

MOFA said in a statement that the letter was “overbearing and unreasonable” and distorted historical facts. It also said the letter violated Article 2, Paragraph 4 of the UN Charter, which prohibits the threat or use of force in international relations.

MOFA said that after the end of World War II, the legally binding San Francisco Peace Treaty superseded the Cairo Declaration and the Potsdam Proclamation. The treaty did not transfer Taiwan to China, and China has never governed Taiwan, the ministry said.

Maintaining peace and stability in the Taiwan Strait has become a consensus within the international community, MOFA said. It cited German Foreign Minister Johann Wadephul’s repeated opposition to the use of force in the Taiwan Strait as evidence that like-minded countries value international law and a rules-based international order.