Chinese President Xi Jinping said on Wednesday that nobody can change the fact that Taiwan is part of China, and that people on both sides of the Taiwan Strait should seek "reunification".
Xi made the comments in a speech on the 40th anniversary of a key policy statement that eventually lead to a thaw in relations with the self-ruled island.
"It is a historical conclusion drawn over the 70 years of the development of cross-Strait relations, and a must for the great rejuvenation of the Chinese nation in the new era," he said.
TRT World's Reagan des Vignes reports.
President Xi said China will not "give up the use of its military force" as an option to ensure the reunification while insisting the island would ultimately be reunified with the mainland.
Beijing "reserves the option of taking all necessary measures" against outside forces that interfere with peaceful reunification and Taiwan independence separatist activities, he said.
Xi said many countries have understood and supported the cause of the reunification of China over the 70 years.
Taiwan defends self-rule
Ahead of Xi's speech Taiwanese President Tsai Ing-wen defended self-rule and said Beijing must respect its sovereignty.
TRT World spoke to Honk Kong-based journalist Samantha Vadas.
"I want to appeal to China that it must admit to the reality of Taiwan's existence and must respect our 23 million people's insistence on freedom and democracy."
She added that China must deal with the countries' differences in a peaceful way as equals, and it must be the government or public agencies that have been authorised by the government that sit down with us and talk.
China views Taiwan as a wayward province, to be brought under its control by force if needed, with no right to international recognition as a separate political entity.
Democratic Taiwan has shown no interest in being ruled by autocratic China.
On January 1, 1979, China declared an end to what had been routine artillery bombardment of Taiwan-controlled offshore islands close to China and offered to open up communications between the two sides, after decades of hostility.
However, the offer was rebuffed by Taiwan's then-president Chiang Ching-kuo, who in April that year came out with a "three noes" policy of no contact, no compromise and no negotiation with China.
Chiang only relaxed that in 1987, allowing people in Taiwan to visit China for family reunions. His father, Chiang Kai-shek, fled with defeated Nationalist forces to Taiwan in December of 1949 after loosing a civil war to the Communists.
No formal peace treaty or formal end to hostilities has ever been signed.