Change Host default gateway without reboot

Hello,

A quick question, I use locally a proxmox host with various CT, default gateway is our IPS1, we have a new one and I want to update the gateway to use IPS2 for host and CT.
Can I just update /etc/networks/interface to change gateway ip and restart network service or should I use proxmox web interface and reboot the whole host.
I prefer to do a quick network restart.

Thank you