Connect istio metrics to external prometheus

Trying a disabled prometheus configuration for istio 1.6 version. Our external prometheus will be used only. Using kube-prometheus for Prometheus installations. Created an additional scrape config as a secret, but wondering how i can mount istio certs to prometheus… The only place i see is prometheus-prometheus.yaml, but sure… In the current situation, in service discovery of Prometheus, there’s no active istio target(0/x active targets). Will you please guide me?