AWS - Connecting 2 VPC regions bi-directional?

I have 2 VPCs, one in US, one in EU, and each of them have 1 VM. (IN US there is the Customer GW (set to irish IP) and Virtual Private GW).

I have succesfully connected with openswan from Irish VM, I can ping Ireland from the US (10.0.0.1) I cannot ping US from Ireland. Why?

Do I need to set up another VPN connection on US VM to have it fully bidirectional? I followed tutorial: https://www.scalefactory.com/blog/2020/12/14/how-to-set-up-a-site-to-site-vpn-connection/

Solution 1:

Problem was restrictive AWS security groups (access lists). After allowing "any any" traffic problem is gone.