China has recalled two cute giant pandas from a popular zoo in the US amid the countries' ongoing trade war.

Bai Yun, 26, and her six-year-old cub Xiao Liwu are iconic images of San Diego Zoo in California.

Bai Yun has spent more than 20 years at the attraction after arriving as a tiny cub. She has aided important worldwide research in the protection, breeding, disease control of giant pandas.

But both majestic animals have been sent back to their native China after the country scrapped its conservation loan agreement with the US.

"They will be under quarantine for a month to help them adapt to the conditions in China," said Zou Wenyong, a spokesman for Dujiangyan Base of the China Conservation and Research Center for Giant Pandas.

 

Little cub Xiao Liwu eats a meal of bamboo at the zoo.

 

But thousands attended a special farewell ceremony to Bai and Xiao at San Diego Zoo last month.

Tourist flew from overseas to the event.

"They are so adorable, and they are always happy and satisfied with their easy lives.

"We had great joy every time we visited them," said Terry Richardson, who attended with her husband.

Erica Kohler, director of operations of the San Diego Zoo, said Bai Yun and Xiao Liwu attracted about two million visitors to the centre each year.

US' agreement with China had for more than 20 years helped bring the animals back from the brink of extinction.

Giant pandas are one of the world's most endangered species.

Fewer than 2,000 pandas live in the wild.