Chinese President Xi Jinping and Russian President Vladimir Putin were on hand as giant pandas Ding Ding and Ru Yi were officially handed over to the Moscow Zoo.  

Ru Yi, a 3-year-old male panda and Ding Ding, a 2-year-old female panda, arrived in Moscow on April 29 and will remain in their new home during a 15-year collaborative research project between the two countries.

Wang Pingfeng, the breeder who was dispatched by the Chengdu Panda Breeding Research Center in southwest China's Sichuan Province, said the two giant pandas have already adapted to their new surroundings. Ru Yi is very vivacious, while Ding Ding is shyer. Breeders at the Moscow Zoo were trained by two breeders from China, who will remain in Russia to monitor the pandas' health over the next month before returning home.

Before the pandas arrived, the Moscow Zoo decorated the panda enclosure and sent two groups of keepers and veterinarians to the Chengdu Panda Breeding Research Center. The center trained them how to feed and take care of the pandas.

The zoo has kept the public updated on news of their new guests via social media. And many excited residents of Moscow, especially children, have been anticipating their debut and visiting the under-construction panda pavilion. 

"It was really hard to keep it a secret," said Moscow Zoo director Svetlana Akulova, "but we are really happy that the people of Moscow are excited about their debut. This year marks the 155th anniversary of the founding of the Moscow Zoo, and it is our great honor to have the pandas."

Akulova said the panda research project aims to further promote giant panda protection and improve conservation of endangered species and the biological diversity of the two countries.