Liz46
Thanks for your help ladies. grandtante, we've tried calling him back when he goes near the fence but he puts two claws up at us. My husband tried lifting him back down but that is not working.
He is a gorgeous cat and very loving. He was the runt of the litter but has quickly grown and is huge now. I think as some of you have said - we're doomed as he will do as he likes.
Liz, the woman opposite me has pedigree cats that are never out of her garden. If you Google, I do believe that you can get sloping fencing to attach to your existing fencing. It would slope inwards (downwards) so the cat cannot climb over it. I hope in his travels that some misguided people don’t start feeding him.