Taiwan's unification with the mainland is "inevitable," President Xi Jinping said yesterday, warning against any efforts to promote the island's independence and saying China would not renounce the option of using military force to bring it into the fold.

China sees Taiwan as part of its territory to be reunified, despite the two sides being ruled separately since the end of a civil war in 1949. "China must and will be united... which is an inevitable requirement for the great rejuvenation of the Chinese people in the new era," Xi said in a speech commemorating the 40th anniversary of a message sent to Taiwan in 1979, in which Beijing called for unification and an end to military confrontation.

"We make no promise to give up the use of military force and reserve the option of taking all necessary means" against Taiwanese separatist activities and "outside forces" that interfere with reunification, he said. In his speech, Xi described unification under a "one country, two systems" approach that would "safeguard the interests and well-being of Taiwanese compatriots." To accommodate differences in Taiwan's political system and civil society, China has proposed adopting the "one country, two systems" policy, which was implemented in Hong Kong after the British handed the city back to China in 1997.

Taiwan considers itself a sovereign state, with its own currency, political and judicial systems, but has never declared formal independence from the mainland. Relations have been strained since the 2016 election of President Tsai, who has refused to acknowledge Beijing's stance that the island is part of "one China."