Earlier, Biden’s administration has reaffirmed its commitment to Taiwan as being ‘rock solid’
China toughened its language towards Taiwan on Thursday, warning after recent stepped-up military activities near the island that "independence means war" and that its armed forces were acting in response to provocation and foreign interference.
Taiwan, claimed by China as its own territory, reported multiple Chinese fighter jets and bombers entering its southwestern air defence identification zone last weekend, prompting Washington to urge Beijing to stop pressuring Taiwan.
China believes that Taiwan's democratically elected government is moving the island towards a declaration of formal independence, though Taiwan President Tsai Ing-wen has repeatedly said it is already an independent country called the Republic of China, its formal name.
Asked at a monthly news briefing about the air force's recent activities, Chinese Defence Ministry spokesman Wu Qian said Taiwan is an inseparable part of China.
"The military activities carried out by the Chinese People's Liberation Army in the Taiwan Strait are necessary actions to address the current security situation in the Taiwan Strait and to safeguard national sovereignty and security," he said.
"They are a solemn response to external interference and provocations by 'Taiwan independence' forces," he added.
Wu said a "handful" of people in Taiwan were seeking the island's independence.
"We warn those 'Taiwan independence' elements: those who play with fire will burn themselves, and 'Taiwan independence' means war," he added.
Taiwan's Mainland Affairs Council said China should think carefully and not underestimate the island's determination to defend its sovereignty and uphold freedom and democracy.
The Chinese incursions coincided with a US carrier battle group entering the disputed South China Sea to promote "freedom of the seas."
China routinely describes Taiwan as its most important and sensitive issue in relations with the United States, which under the former Trump administration ramped up support for the island in terms of arms sales and senior officials visiting Taipei.
President Joe Biden's government, in office for a week, has reaffirmed its commitment to Taiwan as being "rock solid," potentially auguring further strains with Beijing.
Taiwan has denounced China's threats and efforts at intimidation, and Tsai has vowed to defend the island's freedom and not be coerced.