China sailed a carrier group through the politically delicate Taiwan Strait on Sunday, led by the communist country's first domestically built aircraft carrier.

In a statement released Sunday, Taiwan's defense minister announced the military presence in the 112-mile-wide (180-kilometer-wide) strait between the island and mainland China. The naval group progressed from north to south through the strait, trailed by US and Japanese ships, it said.

Taiwan scrambled its own ships and aircraft in order to monitor the Chinese movements.

Read more: Can Taiwan counter China's 'diplomatic aggression'?

Hours before, Taiwanese President Tsai Ing-wen named former Premier William Lai as her running mate in the 2020 presidential elections. Last year, Lai angered China when he expressed his view that Taiwan is a sovereign and independent country. A major Chinese newspaper then called for his arrest.

In a Sunday tweet, Taiwanese Foreign Minister Joseph Wu said Taiwan would not be intimidated.

Warning signal

Self-ruled Taiwan broke away from mainland China in 1949 after communists in Beijing emerged victorious from a civil war.

China considers the democratically ruled island to be part of its territory and has vowed to retake it — using military force if necessary.

The world power has increased pressure on Taiwan in the lead-up to the 2020 presidential elections in January. It has threatened force should the island seek independence.

Read more: Are Hong Kong protests a warning for Taiwan?

Chinese aircraft and ships have repeatedly circled the strait in recent years. In response, in April the US sent two destroyers through the waterway in a sign of commitment to maritime freedom in the region.

Though President Tsai's Democratic Progressive Party is pro-independence, she has called for Taiwanese-Chinese relations to remain as they are, however not at the expense of security and democracy.

China and Taiwan: Best enemies? Recapturing vs. liberation After the end of WWII, the Communist Party of China (CPC) under Mao Zedong pursued a fierce battle against his archrival Chiang Kai-shek, chief of the Kuomintang (KMT) party. Chiang lost and took refuge in the island of Taiwan. For some time after that, Taiwan was the center of propaganda from both sides. The CPC wanted to "liberate" Taiwan, while Kuomintang wanted to "recapture the mainland."

China and Taiwan: Best enemies? Letters to 'compatriots' In the 1950s, the CPC published four "Messages to Chinese compatriots" in Taiwan, which are considered the basis of Beijing's Taiwan policy. In these texts, Beijing warned Taiwan of collaborating with US "imperialists." Military confrontation, particularly artillery attacks, also continued during this time.

China and Taiwan: Best enemies? Beijing replaces Taipei in UN bodies In 1971, the United Nations General Assembly declared that the People's Republic of China was the sole lawful representative of the country. With this decision, the Republic of China (ROC)/Taiwan was removed from all UN bodies. The frustration of ROC's foreign minister, Chow Shu-kai (right), and his ambassador Liu Chieh is easy to see in this picture.

China and Taiwan: Best enemies? New Taiwan policy The fifth and last "message" from Beijing to Taiwan was published on January 1, 1979. The mainland, under the leadership of the reformist Deng Xiaoping ended military operations, announced the development of bilateral ties and promised peaceful reunification. However, Beijing's right to represent China internationally was not to be questioned.

China and Taiwan: Best enemies? 'One China' policy The new orientation of China's Taiwan policy took place as Washington and Beijing got closer. On January 1, 1979, the US and China resumed diplomatic relations, with Washington under President Jimmy Carter recognizing Beijing as the sole legitimate government of the whole of China. The US embassy in Taiwan was remodeled into an institute for culture.

China and Taiwan: Best enemies? 'One China, two systems' Even before meeting US President Carter, Deng Xiaoping had introduced the principle of "one country, two systems," which allowed Taiwan to maintain its social systems even after reunification. However, Taiwan's President Chiang Ching-Kuo did not immediately fall for it. On the contrary, in 1987 he formulated the principle of "one China for the better system."

China and Taiwan: Best enemies? The independence movement In 1986, the Democratic Progressive Party (DPP), Taiwan's first opposition party, was founded. At a meeting in 1991, the DPP declared a clause for Taiwan's independence, which stipulated that Taiwan was sovereign and not a part of China.

China and Taiwan: Best enemies? 'Consensus of 1992' In unofficial Hong Kong talks in 1992, representatives of Taipei and Beijing reached a political agreement on the nature of their relationship. Both parties agreed that there was only one China. However, they had different views on what "One China" meant. A year later, the chief negotiators Wang (left) and Koo met in Singapore.

China and Taiwan: Best enemies? Bilateral relations In an interview with DW in 1995, the first democratically elected President of Taiwan and the KMT leader Lee Teng-hui said that all relations beyond the straits of Taiwan would be "defined as relations between states; at the very least, as a relationship of a special kind between states." His formulation was very close to being a declaration of independence.

China and Taiwan: Best enemies? 'A state on every side' The DPP won the presidential election for the first time in 2000 with Chen Shui-bian, a Taiwanese-born politician who had no connections to mainland China, calling for "a state on each side." It meant that Taiwan should have nothing to do with China anymore. In 2005, Beijing reacted with the Anti-Secession Law, which allowed the use of military force in the event that Taiwan declared independence.

China and Taiwan: Best enemies? 'One China, different interpretations' After losing the elections in 2000, the KMT adopted a changed formulation of the "Consensus of 1992" in the party's statute, which called for "one China, different interpretations." That is why the 1992 Consensus is still debated in Taiwan. The reason: the negotiators of 1992 did not have an official position.

China and Taiwan: Best enemies? CPC meets KMT The mainland adopted the "Consensus of 1992" as a political basis for creating a relationship with Taiwan. In the first summit between the two sides since the communists came to power in China, Hu Jintao (right) and Lian Zhan endorsed the "Consensus of 1992" and the "One China" principle.

China and Taiwan: Best enemies? 'The direction is correct' After KMT's Ma Ying-Jeou won the 2008 presidential elections, both sides continued to come closer. In an interview with DW in 2009, Ma said: "The straits of Taiwan should be a place of peace and security. We have come a lot closer to this goal. Basically our direction is correct."

China and Taiwan: Best enemies? Quo vadis? After the elections in 2016, when President Tsai Ing-wen came to power, the independence movement gained a lot of wind. Tsai disputed the existence of the 1992 consensus and described the "attempt of China to interfere in the political and social development of Taiwan" as the "biggest challenge." Author: Fang Wan (mg)



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