Two giant pandas departed China for a zoo in the US capital on Monday, a Chinese conservation group said in a statement.
Bao Li, a male panda, and female Qing Bao, both three years old, were headed to the Smithsonian National Zoo in Washington under a decade-long breeding and research agreement.
"China and the United States have made orderly arrangements... to ensure that the two giant pandas will arrive at the Washington National Zoo safely and smoothly," the China Wildlife Conservation Association (CWCA) said in a statement.
Only a few of the beloved black-and-white bears remain in the United States after almost all were returned to China in recent years under pre-arranged contracts -- including all three of the National Zoo's pandas last November.
The lack of immediate replacements was viewed by many as a symbol of the heightened tensions between Washington and Beijing.
China has been using so-called "panda diplomacy" since 1972, when the first animals were sent to Washington as a gift, following US president Richard Nixon's historic visit to the Communist nation.
Chinese President Xi Jinping said after meeting his counterpart Joe Biden at a summit in California last November that China could send new pandas as "envoys of friendship between the Chinese and American people."
In August, the San Diego zoo welcomed two new giant pandas, the first to be sent by China to the United States in 21 years.
Anticipation for the pandas' arrival in Washington was high, with the National Zoo's website emblazoned with a banner that read: "The pandas are coming."
Something "giant" is "coming to Washington," the zoo said in a post on X, formerly Twitter, adding that it would be closed on Tuesday but that for "the safety of the pandas and staff, we will not disclose any additional timing."
Preparations were well underway at the zoo, where pandas have been star attractions for decades.
Renovations have been undertaken at the panda habitat "to enhance the safety of the facilities and maximize space for the bears to roam," according to the zoo's website.
The new structures constructed for the pandas include shallow pools to allow them to bathe and bamboo stands that require the bears to mimic the foraging techniques they would use in the wild.
The bears will not, however, be available to the public for more than a month after their arrival, as they will need to be quarantined and to acclimate to their new habitat.
While en route, the pandas' in-flight meals will include bamboo shoots, carrots and Chinese cornbread, the conservation association said.