Disable site one-step authentication

Hello,
I have successfully enabled two-step authentication for logging into my website using my wordpress.com account.
But – in the site’s login page, I can still choose ‘log in with username and password’.
I want to remove this option completely, so that users can only log in using two-step authentication.
I have posted this question in the wordpress.com forum, but I was told to post here instead, since my website is self-hosted with www.ads-software.com.

Thanks a lot, Gilad.