33-year-old Liddle has made sixteen first-team appearances since he joined the Saddlers back in the summer, and has found it hard to tie down a permanent spot in Darrell Clarke's side.
Liddle spent six years at the Pools' Victoria Park between 2006 and 2012 and will join up with the club immediately and could feature against Dagenham & Redbridge, subject to clearance.
We would like to join Walsall FC in wishing Liddle well for his spell in the North East.