Japan returned its twin pandas to China amid a diplomatic row between the two countries.

Beloved pandas Xiao Xiao and Lei Lei, both aged four, departed Ueno Zoological Gardens in Tokyo by truck as they were repatriated to China on January 27.

Footage shows locals on the roadside bidding farewell to the pair as the truck headed for Narita International Airport.

Waving flags printed with the twins' faces, residents called out 'Take care!' as the vehicle sped by.

Xiao Xiao and Lei Lei, both born and raised in Japan, had a public viewing on Sunday before their scheduled return to China.

They are set to arrive at a conservation centre in Sichuan province on Wednesday, January 28, leaving Japan without pandas for the first time since 1972.

Both pandas were loaned out as part of China's 'panda diplomacy', which involves lending giant pandas to foreign zoos as a soft power to strengthen diplomatic ties.

The abrupt return came following Japanese Prime Minister Sanae Takaichi's remarks that a Chinese attack on Taiwan could constitute a 'survival-threatening situation', potentially necessitating military action.

China views Taiwan as a breakaway province and has consistently pursued reunification, including the use of force.