Private key export for SSH

[John Lane]

I've been trying out the SSH compatibility. Everything working as per
the documentation, except I have one question.

How can I extract the SSH PRIVATE key ?

I am using "gpg --export-ssh-key alice > ssh_key.pub" for the public key
but I can't find an equivalent for the private key.

The reason why I would like the private key is so that I can use it on
another host where I don't have the benefit of gpg 2.1 (or any gpg, for
that matter).

Thanks,
John