The boss of one of the UK's biggest banks says it is being attacked "all the time" by online criminals and he is kept up at night by cyber threats.
"It does keep me awake," HSBC UK chief executive Ian Stuart told the Treasury Committee of MPs.
"Because we can be attacked and we are being attacked all the time."
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Mr Stuart said banks were spending "enormous" sums of hundreds of millions of pounds on IT systems - the biggest expense in their businesses.
"Cybersecurity is now very much at the top of our agenda," he added.
Concerns were also highlighted by Lloyds Bank chief executive Charlie Nunn, who said financial fraud will get worse if banks cannot intervene to prevent it and social media and telecoms companies are not incentivised to halt it.
Mr Nunn said the UK "has become the home of fraud", adding that the number of victims is "pretty disturbing" and "individual cases are harrowing".
Major high street businesses, including M&S and the Co-op, have been hit by cyber attacks in recent weeks and had their operations impacted.
Cybersecurity threats, however, were not behind the several-day outage at Barclays at the end of January, its UK chief executive Vim Maru said.
He added: "We've learned the lessons. We're acting on the lessons, both work done internally, but also with help from third parties as well.
Account holders across the UK have suffered a spate of IT glitches from different banks around paydays this year.
Tens of millions of pounds on IT have been spent and customer glitches have fallen, Mr Maru said.
He added that the problem at Barclays was a software issue, saying: "We put a fix in place that means that we won't have a recurrence."
(c) Sky News 2025: HSBC 'being attacked all the time' by online criminals - as boss 'kept awake at night' by cyb
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