The mayor of Buenos Aires has announced that his administration has taken over the running of the city's zoo after a series of scandals about the condition of its animals and buildings.
It will now become an eco-park promoting environmental conservation.
Its 2,500 animals will be moved to sanctuaries in other parts of Argentina and abroad where they can be housed in better conditions.
Mr Larreta said the animals had been living in degrading conditions.
The zoo has been in existence since 1875, run by a private company which won a concession to manage it.
The zoo attracted very bad publicity in recent years, particularly over the inadequate conditions in which its polar bears were kept during the city's oppressively hot summers.
The last polar bear, called Winner, died three and a half years ago during a particularly hot season.
Among the 50 animals who will stay behind because they are too fragile to move is Sandra, an Orang-utan who made headlines two years ago.
Animal rights activists won a legal case in which she was granted the status of a "non-human with rights" after concerns were raised about her health and living conditions.