A giant panda gifted by China to Taiwan has given birth to a second female cub after being artificially inseminated, Taipei Zoo announced Monday.

Yuan Yuan and her partner Tuan Tuan have been top attractions since arriving from China in 2008, having been sent as a symbol of what were then warm relations between the two sides.

The unnamed cub, weighing 186 grams (6.56 ounces), was born Sunday after five hours of labor, the zoo said.

"We were hoping the mother could look after the cub. But Yuan Yuan was probably very tired from the birth," the zoo said in a statement, noting that caretakers took over and fed the newborn themselves.

The cub is in stable condition after being treated for a minor injury to its back, the statement added.

Yuan Yuan gave birth to a daughter, Yuan Zai, in 2013 – the first giant panda born in Taiwan.

Beijing usually only loans its pandas, and any progeny must be sent to China.

But in a rare departure from that protocol, Taiwan was allowed to keep Yuan Zai as her parents were a gift, according to Taipei officials.

China's decision to give Tuan Tuan and Yuan Yuan to Taiwan was a symbolic gesture when the self-ruled island was run by the Beijing-friendly Kuomintang administration.

"Tuanyuan," a combination of the Chinese characters of the pandas' names, means "reunion" or "unity."

The pair's arrival sparked panda mania on the island, especially after Yuan Zai's birth.

Taiwan and China have been ruled separately since the end of a civil war in 1949. Beijing has vowed to one day bring the island back into its fold, by force if necessary.

Since the 2016 election of President Tsai Ing-wen, who views Taiwan as a de facto sovereign state and not part of "one China," Beijing has ramped up military, economic and diplomatic pressure.

Fewer than 1,600 pandas remain in the wild, mainly in Sichuan province, with around 300 in captivity around the world.