Upvote:1
According to UkImmigrationSpecialist:
If you are applying in the country of which you are a citizen, you can submit applications in any UK visa category. If you are not; the following rules apply:
Applications for transit visas, visit visas, and EEA Family Permits may be submitted in any country offering a UK Entry Clearance (=visa) service.
So the answer is: yes, you may submit your application in Italy without having a regular residency permit. It would even be possible on a tourist visa, assuming you had enough time to wait for the processing.