Banks are running short of British pound banknotes as Kiwis take advantage of a massive slump in the currency's value following Britain's shock decision to leave the European Union.
The New Zealand dollar was trading at 52.94p this afternoon, which is close to a three-year high.
An ANZ spokesman said demand for sterling had been "several times higher" than normal.
He said a number of branches had been affected by a shortage of banknotes available from suppliers.
"We're sourcing additional notes and supplying affected branches as stocks become available and expect supply volumes to be back to normal by next week," the spokesman said, adding that customers could continue to buy pounds with prepaid travel cards or through a foreign currency account.