Xi Jinping told visiting Taiwanese opposition leader Cheng Li-wun China would “absolutely not tolerate” independence for the self-governed island and reiterated his call for its “reunification” with the mainland.

In a rare meeting with a Taiwanese political leader, he claimed people on both sides of the Taiwan Strait were Chinese and wanted peace.

Though Taiwan has its own democratically-elected government, China claims sovereignty over the island and has threatened to “reunite” it with the mainland by force if necessary. China has recently ramped up military and political pressure against the island.

“Compatriots on both sides of the strait are all Chinese, people of ⁠one family who want peace, development, exchange, and cooperation,” he said, adding that the mainland and Taiwan both belonged to “one China”.

“When the family is harmonious, all things will prosper,” he said. “Taiwan independence is the ⁠chief culprit in undermining peace in the Taiwan Strait. We will absolutely not tolerate or condone it.”

Ms Cheng, chair of the Kuomintang (KMT) party, said Taiwan should “no longer be a flashpoint for potential conflict” but “a symbol of peace jointly safeguarded by Chinese people on both sides of the strait”.

She also said the “rejuvenation of the Chinese people is a shared aspiration of the people on both sides of the strait”.

Mr Xi said the KMT and the Communist Party of China “must consolidate political mutual trust, maintain positive interaction, unite compatriots on both sides of the strait, and join hands to create a bright future of the motherland’s reunification and ‌national rejuvenation”.

Ms Cheng’s visit has sparked a backlash in Taiwan, where many people see China as a threat.

Her party ruled all of China but fled to Taiwan after losing the civil war in 1949 to Mao Zedong’s communists, leaving the sides without a peace deal and still not formally recognising each other.

Ms Cheng called for mutually beneficial ties and said Taiwan should not be a “chessboard for outside forces”.

Taiwan relies on the US as its main backer and arms supplier, which is a source of continuing tension with China.

Her meeting with Mr Xi came amid deep political divisions in Taiwan. While Ms Cheng and her party argue that engagement with China reduces the risk of a military takeover, president Lai Ching-te and his Democratic Progressive Party favour a stronger stance amid rising pressure, including expansive military drills around the island, from Beijing.

Beijing has previously described Mr Lai as a “separatist” and a “troublemaker”.

Speaking in Taipei on Friday, the ruling party’s general secretary Hsu Kuo-yung criticised the KMT for delaying parliamentary approval of defence spending while Ms Cheng was in China. “Are you trying to give some kind of grand gift to Xi Jinping?” he asked.

While the KMT has traditionally maintained warmer ties with Beijing, analysts note, Ms Cheng has taken a more forward-leaning approach than her predecessors.

Taiwan’s top China policymaker, Chiu Chui-cheng, told reporters: “The Chinese ⁠communists are deliberately creating the false impression that Taiwan is an internal affair of China.” He added that only Taiwan’s people could decide their future and that China should engage with Taipei’s democratically elected and legitimate government.