SAN DIEGO -- The San Diego Zoo is preparing to say farewell to its last two giant pandas.

The zoo said Monday that 27-year-old Bai Yun (bye-yoon) and her 6-year-old son, Xaio Liwu (shyaoww-lee-woo), will depart as planned next month for China. A multiyear agreement with the Chinese is coming to an end.

April 27 is the last day pandas can be viewed by the public.

The departure will mark the first time in more than two decades that the zoo will be without the black-and-white bamboo-eating bears.

Officials couldn't immediately say when or if pandas may inhabit the zoo again.

There are still pandas at Smithsonian's National Zoo in Washington, DC, Zoo Atlanta and the Memphis Zoo. (AP)