China is planning to donate a pair of crested ibises to Japan in October as a symbol of friendship — the first such donation in more than a decade — amid warming relations between the two countries, Japanese government sources said Wednesday.

The two countries are making arrangements for the transfer of the internationally protected species to the Sado Japanese Crested Ibis Conservation Center around Oct. 23, when Prime Minister Shinzo Abe is expected to visit China to celebrate the 40th anniversary of a bilateral peace and friendship treaty taking effect, the sources said.

Since Chinese Premier Li Keqiang promised to provide the birds to Japan during his visit to Tokyo in May, officials from both countries have been coordinating when to bring the pair to the conservation facility in Niigata Prefecture.

It would be China’s first transfer of the endangered birds to Japan since November 2007.

Abe is expected to convey the country’s gratitude over the donation when he visits China.

Chinese officials have been checking to see whether the ibises are infected with bird flu or other diseases, before making a final judgement over whether to send them to Japan, the sources said.

The two, if they prove to be healthy, will likely arrive at the conservation center on Sado Island before or after Oct. 20 from China’s northern province of Shanxi, they said.

Japanese-born ibises became extinct in 2003. Since then, Japan has been artificially breeding the birds for reintroduction into the wild by relying on Chinese donations, the first of which was in 1999.

China’s offering of the rare species often reflects bilateral political conditions.

In 2011, then Chinese Premier Wen Jiabao expressed Beijing’s intention to offer ibises to Japan, but the plan was shelved after a diplomatic dispute escalated in the wake of Tokyo’s decision a year later to put the Senkaku Islands in the East China Sea under state control.

Although China continues to claim the uninhabited islands, which it calls Diaoyu, ties between Tokyo and Beijing have warmed in recent years.

On the sidelines of a regional economic forum earlier this month in Russia, Abe and Chinese President Xi Jinping agreed again to step up efforts to improve relations between the two countries.