Giant pandas Yun Chuan and Xin Bao set out on their journey to the United States on Wednesday evening, marking a new round of China-US cooperation on the conservation of the protected species.

A vehicle carrying the panda bears departed from the Ya'an Bifengxia Base of the China Conservation and Research Center for the Giant Panda in Sichuan province. They will board a chartered flight from Chengdu Shuangliu International Airport to San Diego in the US state of California.

The pandas are accompanied by five experienced caretakers and veterinary experts from China and the US. To ensure the health and safety of the animals during the long-haul flight, Chinese experts have arranged food, such as fresh bamboo, bamboo shoots, fruits, vegetables and specially made bread, and drinking water.

After Yun Chuan and Xin Bao settle in at the San Diego Zoo, Chinese experts will stay there for about three months to see them through the quarantine period, helping them to quickly adapt to their new living environment. Panda enthusiasts in both China and the US will have various means of learning about the pair's daily lives and adjustment process, according to the National Forestry and Grassland Administration.

Since the 1990s, China has collaborated on giant panda conservation with 26 institutions in 20 countries, including the US, Spain, Japan and France.

The San Diego Zoo was one of the first institutions in the US to engage in cooperative research on giant pandas with China. Over more than 20 years, the two sides have cooperated and solved a series of technical challenges in key areas such as captive panda breeding, habitat protection and panda supplemental nutrition, according to the Sichuan center.

On the same day when Yun Chuan and Xin Bao set out for the US, the China Wildlife Conservation Association and the Schoenbrunn Zoo in Vienna, Austria, signed an agreement on a new round of international cooperation on giant panda conservation. It means another pair of panda bears will move to the European country, initiating a 10-year international cooperation on giant panda conservation.

Giant pandas Yuan Yuan and Yang Yang, who are currently in Austria, will return to China once the previous cooperation agreement expires this year. Austria will renovate the Vienna zoo's panda enclosure and make other necessary arrangements to welcome the new pair to a more comfortable and safer living environment.

To ensure the well-being of the giant pandas, Chinese experts visited Austria at the start of this year and provided technical guidance on venue preparations, specifying standards for panda enclosure facilities, feeding management, food supply, healthcare and other requirements.

The China Wildlife Conservation Association and the Schoenbrunn Zoo, which is renowned as one of the most beautiful zoos in Europe, started their first phase of cooperation in 2003, with the arrival of giant pandas Yang Yang and Long Hui at the zoo. The pair set a European record by mating naturally and breeding four times to become the parents of five cubs.

Over the past two decades, both sides have achieved fruitful results in giant panda conservation, breeding, scientific research, technical exchanges, personnel training and public education, according to the Sichuan center.