Strong thin cutting wire (Kemptown BN2)

Hi,

I’m trying to remove a bathroom mirror (approx. 50 × 50 cm) that’s been fixed to the wall with double-sided tape or glue.

I’m looking for something thin but strong that can be fed behind the mirror and used to cut through the adhesive/double sided tape — for example:
• Fishing line
• Piano wire
• Guitar string
• Strong nylon line
• Or anything similar

Floss isn’t strong enough, and rigid tools with handles can’t reach far enough behind the middle of the mirror to be effective. A flexible cutting line or wire would be ideal.

Happy to collect locally.

Thanks in advance.