BGP injecting routes on ASA Firewall

DevilWAH

Hi, 

I know i can do this just cant remember how! 

On an ASA firewall i need to advertise a route out to a BGP neighbor. However as the network I am advertising is down a ipsec tunnel link there is no route to it in the routing table. 

If i add a route to null then it stop traffic getting passed down the tunnel completely. So is there any way to send a route to a BGP neighbor that is not in the routing table?

Cheers