GKE private and vault auth

Hi Pïps
I have been working on kubernetes auth method for Vault . Vaullt is not able to connect to my GKE private cluster endpoint as It is only accessible through API proxy. Is there any way we can pass proxy in the below command:
$ vault write auth/kubernetes/config
token_reviewer_jwt=“reviewer_service_account_jwt”
kubernetes_host=“”
kubernetes_ca_cert=@ca.crt