Around 200 people formed a human chain in a French zoo Sunday to call for a reprieve for two ailing elephants whose death sentence has led Brigitte Bardot to threaten to go into exile in Russia.

"Justice for the elephants," chanted the crowd as they surrounded the cage in which Baby and Nepal live in the Tete d'Or zoo in Lyon.

The two elephants face being put down because they have been diagnosed with tuberculosis and deemed a threat to the health of other animals and visitors to the zoo.

Authorities in the central city ordered the elephants be put to sleep last month, prompting an outcry that resulted in them being granted a temporary reprieve over Christmas.

Cinema legend Bardot said on Friday that she would leave France if the reprieve was not made permanent.

In a surreal twist to the saga over fellow actor Gerard Depardieu's move into tax exile, the veteran animal rights campaigner said she would emulate his adoption of Russian nationality unless authorities intervened to save Baby and Nepal.