Way to broadcast ARP to uplink router?

[R0ut3r]

Is there a built-in way (without using ARP cache poisonning techniques) to tell the upstream / uplink router the ARP for Nat'ed IPs on the FW.

Essentially, the IPs being NAT'ed by the FW have been in use on hosts directly connected to the uplink / upstream router and that router needs it's ARP cache updated.

When the router is not controlled by the ISP, this is as simple as clearing the cache directly on the router, when it isn't however, ungraceful power cycling or calls to ISP support need to happen. I'm looking for a way to avoid this.

The current, only way I have found to do so is to hook-up another machine to the public segment and do ARP cache poisonning. That's not exactly graceful either.

Thanks