AWS IPSec VPN lacking a route

On our XG330 v2 18.5.1 MR-1 Following the various guides, I have set up a VPN to AWS using their (supplied by a third party whose VPC it is) generic config file.

The VPN is active and connected but the local host has no route to the remote subnet. 

• Looking on the CLI, route -n does not have a route to the remote subnet
• system ipsec_route show is empty

Does this also need a static route from our internal subnet to the remote subnet?  If so what gateway/interface to use?

Thanks in advance

Jon