London (CNN) Margaret Thatcher was apparently not one for panda diplomacy.

The former British Prime Minister once refused to share a flight to Washington with a giant panda on an official visit, according to official documents declassified on Friday .

In 1981 the president of the London Zoological Society, Lord Zuckerman, asked officials if Thatcher would take a male panda named Chia-Chia to the United States on her Concorde flight.

Chia-Chia the panda was given to Britain by the Chinese Government in 1974.

The Smithsonian Institute in Washington had requested the panda to be loaned from London Zoo so that it could mate with its resident female panda.

"Lord Zuckerman sees this as a signal demonstration of the special relationship," Cabinet secretary Robert Armstrong wrote in a letter to the Prime Minister's private secretary.

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