People across the Taiwan Straits have expressed sadness over the death of Tuan Tuan, the giant panda gifted by the Chinese mainland to Taiwan that symbolized peace, unity and amity.

The 18-year-old male, one of two giant pandas gifted in 2008 died at 1:48 pm on Saturday, Taipei Zoo announced.

In 2005, the mainland announced its intention of sending a pair of pandas to Taiwan as a goodwill gift. Their combined names, which read as Tuan Yuan or "reunion", were announced by audience vote during the annual Chinese New Year Gala in 2006.

Tuan Tuan and his mate, Yuan Yuan, have been popular since they arrived at Taipei Zoo in 2008.They have had two cubs, one in 2013 and another in 2020. In return, Taiwan sent a pair of indigenous goats and a pair of spotted deer to the mainland in 2011.

"Fourteen years ago, their arrival in Taiwan was a significant symbol of the development of peaceful relations between the two sides," Zhu Fenglian, spokeswoman for the State Council's Taiwan Affairs Office, said in a statement on Saturday.

"For years, they have brought joy and good memories to our compatriots in Taiwan," Zhu said, adding that people from both the mainland and Taiwan were expressing condolences and recalling their memories of Tuan Tuan in different ways.

The panda's death became a hot topic on microblogging platform Weibo over the weekend. Many netizens recounted their memories of voting for the pair's names.

Netizens from Taiwan also wrote comments mourning Tuan Tuan on social media, among them one that read "Thank you Tuan Tuan for bringing me such sweet childhood memories".

Taipei Zoo spokesman Tsao Hsien-shao, said the zoo plans to hold an event in memoriam of Tuan Tuan's life, according to island media.

Taipei Mayor Ko Wen-je thanked Tuan Tuan in an Instagram post for bringing happiness to Taiwan people and making Taipei Zoo a more wonderful place.

The office of Ma Ying-jeou, a member of the opposition Kuomintang and the leader of the island from 2008 to 2016, issued a statement on Saturday expressing condolences, saying that the pandas represent a period of communication across the Straits and the sincere interaction of people on both sides.

The statement expressed the hope that there would be more Tuan Tuans in the future, contributing to the integrated development of both sides and that the Tsai Ing-wen administration would promote exchanges across the Straits.

Suspected of having a brain tumor, the panda began suffering seizures in August, and had appeared increasingly lethargic and unsteady on his feet in recent months, arousing concerns.

The China Conservation and Research Center for the Giant Panda in Sichuan province convened an expert team to communicate online with Taipei Zoo and sent two experts earlier this month to Taiwan to assist with the diagnosis and treatment.

The animal had been experiencing frequent seizures since Thursday, and suffered a further spate in the early hours of Saturday morning until 7 am, when veterinarians administered anti-seizure and calming medications.

The zoo said that the panda was anesthetized and given a CT scan, after which the team decided to let Tuan Tuan continue to sleep when the results indicated the panda's condition was irreversible and it could no longer live a quality life.

Zhu thanked the teams on both sides, the zoo and all parties concerned for their efforts in treating the panda, and expressed the hope that the two sides would continue to cooperate in the protection of giant pandas.