I have a cable inside the wall box of a light switch in the UK and it is not connected to anything but it is live. The wires are sitting inside plastic connector/strip. Upon opening up the connector, I found that none of the wires were stripped back. Black wire reads about 150 V ac to earth on the same cable and I believe the reason for this is poor earth connection on the other end at junction box. Should I remove this "unused" cable while I still have my floor boards lifted for safety reasons?
If the two wires haven't been stripped, and have been shoved into a terminal block, then they must be spare wires. Presumably they used to do something. By shoving them into a terminal block, it keeps them safe, so they can't touch anything else.
If you're certain they are no longer needed, then you could remove them, but you would have to work out where they go first.