It is "arrogant and ignorant" to call Taiwan a country and its future can only be decided by China's 1.4 billion people, Chinese Foreign Ministry spokeswoman Mao Ning said, quoted by Reuters.
Her statement was in response to the words of the democratically-ruled island's foreign minister.
China considers Taiwan its territory and claims that the island is one of its provinces and has no right to be called a country. He has stepped up military and political pressure to back up those claims, including increasing the intensity of military exercises.
Taiwanese Foreign Minister Lin Chia-lung said yesterday that China has no authority to decide whether Taiwan is a country because the island chooses its own government. He added that he would be happy to shake hands with his Chinese counterpart Wang Yi as a sign of friendship.
However, the Chinese Foreign Ministry spokeswoman stressed that Taiwan has never been a country.
"Relevant comments only reveal someone's arrogance and ignorance and are naked provocations for Taiwan independence," she pointed out.
"The future of Taiwan can only be decided by the 1.4 billion Chinese people, including our Taiwanese compatriots, and China will and must reunify, which is a historical trend that no force can stop," Mao added.
Taiwan's official name is the Republic of China - the name of the government that in 1949 fled to the island after losing a bloody civil war with Mao Zedong's communists, who established the People's Republic of China.
In a video released yesterday, Taiwan's President Lai Ching-te told military officers that "precious" freedom and democracy must be protected with force and constant vigilance.
"Freedom and democracy are not gifts that fall from the sky; they are the fruits of the perseverance and sacrifice of generations of brave people," he said.
Lai, who China calls a "separatist," is marking his first anniversary in office this week. China has rejected his repeated offers of talks.