Keepers at Banham Zoo are celebrating their first arrival of Pallas cat kittens.

Four kittens were born at the attraction at the end of April and have recently emerged from their nest box.

Staff at the zoo had been hoping their secretive Pallas pair would breed since 2009 when a male arrived from Jihlava Zoo, Czech Republic to join the female as part of the European Breeding Programme.

Pallas cats are classified as 'near threatened' in the wild because of over hunting and poisoning and inhabit parts of central Asia and northern China. There are currently 125 Pallas cats in the European programme.

A zoo spokesman said: 'Having to keep it a secret since April has been so difficult, we didn't even know for certain that our female definitely had kittens until for first one was seen approximately 34 days after birth when a keeper briefly spotted two little heads poking out of the nest box, it was then a few more days before we saw all four out together'

'The kittens have now reached an age where their susceptibility to the disease is reduced and they are old enough to be given access to the main enclosure at the zoo.'

When the kittens are old enough they will depart to other European zoos, but it is likely that they will remain at the zoo until 2013, said the spokesman.