Retry to remote DC if all the replicas are unavailable in local DC

[Ganesh M]

Hi cpp driver has provided Downgrading Consistency Retry Policy which will retry at the cost of lower consistency.

But what if all the replicas in local DC are down?
Is there a retry policy which will execute the same query in remote DC with same consistency or lower?

If not what can be the optimal way to solve this without much application changes?

Thanks
Ganesh