Panda twins Lei Lei and Xiao Xiao are due to be transported by truck out of Ueno Zoological Gardens, their birthplace, disappointing many Japanese fans who have grown attached to the four-year-olds.

"I feel like seeing pandas can help create a connection with China too, so in that sense I really would like pandas to come back to Japan again," said Gen Takahashi, a 39-year-old Tokyo resident who visited the zoo with his wife and their two-year-old daughter.

The pandas' abrupt return was announced last month during a diplomatic spat that began when Japan's conservative Prime Minister Sanae Takaichi hinted that Tokyo could intervene militarily in the event of any attack on Taiwan.

Her comment provoked the ire of Beijing, which regards the island as its own territory.

The distinctive black-and-white animals, loaned out as part of China's "panda diplomacy" programme, have symbolised friendship between Beijing and Tokyo since the normalisation of diplomatic ties in 1972.

Ueno Zoo invited some 4,400 lucky winners of an online lottery to see the pandas for the last time on Sunday.

Passionate fans without tickets still turned out at the park, sporting panda-themed shirts, bags and dolls to demonstrate their love of the animals.

The repatriation of the pandas comes a month before their loan period expires in February, according to the Tokyo Metropolitan Government, which operates Ueno Zoo.

Tokyo has reportedly been seeking the loan of a new pair.

China has discouraged its nationals from travelling to Japan, and is reportedly choking off exports of rare-earth products crucial for making everything from electric cars to missiles.

However, China routinely removes pandas from foreign countries and the latest move may not be politically motivated, said Masaki Ienaga, a professor at Tokyo Woman's Christian University and an expert in East Asian international relations.

Even if the spat is to blame, he said pandas could return to Japan if bilateral ties warm.

"In the future... if there are intentions of improving bilateral ties on both sides, it's possible that (the return of) pandas will be on the table", he told AFP.