Registered SSH key can't be recognized from terminal

I followed the instrutions to get an SSH key and registered it online.
If I do:

bzr lp-log

It shows me my user id. When I try to build chromium on ubuntu using this command:
bzr branch lp:chromium-browser

I get this error message:
Permission denied (publickey).
ConnectionReset reading response for 'BzrDir.open_2.1', retrying
Permission denied (publickey).
bzr: ERROR: Connection closed: Unexpected end of message. Please check connectivity and permissions, and report a bug if problems persist.

I'm pretty sure the key is registered but somehow the computer doesn't recognize it. How should I got about this?