HSBC cash machines stopped functioning for nearly four hours on Friday, after one of the bank’s mainframes crashed.

The problem emerged at 11.45am and the mainframe was running again four hours later. But HSBC declined to comment on what supplier’s technology was affected, or how it was fixed.

A spokesperson at the bank said: "HSBC experienced a brief issue with a number of its systems, including internet banking and its ATMs. The problem was investigated and quickly resolved, meaning systems were up and running again very shortly."

The outage marks the second system crash affecting HSBC cash machines in recent months. In June, another undisclosed technology problem is understood to have prevented customers from being able to use ATMs and online banking.

HSBC is standardising its IT globally under the cost-cutting 'One HSBC' strategy. It is not known whether the changes played any part in Friday’s mainframe problems.

The bank is also cutting thousands of operational and IT staff . And last month, following an efficiency review, HSBC cancelled plans to construct a £300 million datacentre in York.