Really? Does that mean some young are back from Whipsnade? [For several years, London has only had a single adult female Egyptian tortoise (Testudo kleinmanni) on exhibit.]
I'd have said this looks more like a young T. hermanni or perhaps T. graeca.
Merely suggestion on my part as early last year - when I visited the London Zoo Reptile House - those boards on Kleinmann's tortoise were still up. And yes it does look more like a T. hermanni from the picture.
Bongorob you were right first time round. Sorry for the confusion here!