Zoo staff said the expectation was based on the behaviour of Lin Hui, which was a gift from China, such as the animal licking its body and preparing its habitat as if for a cub.

Staff said the signs indicated that the artificial insemination with the semen of the panda Chuang Chuang had been successful, adding that the panda was expected to deliver the cub on June 16, the 40th anniversary of the zoo.

If the panda does give birth to a cub, it would be its second and also the second born in Thailand after Lin Ping was born at the zoo in 2009. Lin Ping was transferred to China in 2013 to be paired with a mate.

Lin Hui is now living in an area at the zoo where visitors are not allowed to give the animal space and reduce ambient noise.

Zoo staff and animal lovers are hoping that the expectation bears fruit after multiple unsuccessful artificial attempts.