Cannot access gitlab remote through ssh

[Alessandro Astone]

My ssh key was about to expire on gitlab, so I removed it and added it 
again (this time without an expiration date).
Now I find myself unable to fetch/push at git at gitlab.freedesktop.org:* 
from a PC with only that ssh key installed.
`git fetch --verbose` does not print anything, and never returns.
I am still able to push from another machine with a different key.

My account is 'aleasto', affected key is labeled 'ubuntu'.