Istio mtls for aws alb

I have installed istio minimal in my eks cluster and i am using aws alb controller for my ingress. Without mesh my ingress is able to talk to the pod exposed via a service at port 80.

On adding the mesh it throws a 502 error from alb.

My implementation looks like internet → Load balancer (HTTPS) → kubernetes service → Pod(meshed).

My goal is to achieve end to end TLS encryption and I dont want to use istio gateway or ingress gateway.

How can i fix this or is it mandatory to have ingress gateway for such a scenario?