Use nslookup to find the IP address for storage.googleapis.com

Negotiate with the security team to assign a public IP address to the servers

Restrict egress traffic from these servers to only the IP addresses for storage.googleapis.com

Establish a Cloud VPN tunnel to a Google Cloud VPC

Deploy a Compute Engine instance within this VPC and install the Squid proxy server

Configure your servers to route traffic through this proxy for Cloud Storage access

Transition the servers to Compute Engine

Set up an internal load balancer (ILB) with storage.googleapis.com as the backend

Direct your new instances to use this ILB as a proxy

Create a secure tunnel to a Google Cloud VPC using Cloud VPN or Interconnect

Utilize Cloud Router to advertise a custom route, announcing this network to your on-premises network via the VPN tunnel

Configure your on-premises DNS server to resolve *.googleapis.com as a CNAME to restricted.googleapis.com