Canterbury police are searching for a man who stole a "treasured Pounamu carving" from inside the Hanmer Springs pools early on Saturday morning.

Security footage of the robbery shows an individual approach the Pounamu held within the Hanmer Springs Thermal Pools and Spa complex, break it off a stand and then wander off with the treasure.

"Staff and visitors are absolutely devastated and would love for it to be returned," Canterbury police say.