how to pass ssh options to git?

How is it possible to pass ssh options to git?
for example, I use these options to log into some machine:
ssh -i <private> -o HostKeyAlias=<alias> -p <port> -l <user> <address>

However, git will only let me specify the user name on command line as part of
the URL.  I am guessing something can be done using core.gitProxy?



--