psql connect over ssl load balancer

Hi.

I want to secure connections to postgress server usings SSL.
My server is deployed on google cloud behind SSL load balancer, which 
terminates SSL connections (using SSL certificates, issued by google) 
and forwards decrypted traffic to the posgres server.

I can connect without problems from nodejs using TLS socket.

But standard psql client don't working:

$ PGSSLMODE=require psql -h proxy.softvisio.net

psql: error: connection to server at "proxy.softvisio.net" 
(34.149.158.159), port 5432 failed: server closed the connection 
unexpectedly
         This probably means the server terminated abnormally
         before or while processing the request.


Seems, that psql will not work withour private keys? But I am not sure.

Could somebody help me to understand, how I can use it?