Andrew Tyrie, the chairman of the Treasury Select Committee, has demanded answers from Royal Bank of Scotland (RBS) boss Stephen Hester about the bank's ongoing computer failures.
Since last Thursday, millions of customers of RBS, Natwest and Ulster Bank have been unable to transfer money in or out of accounts because of IT problems.
In a letter sent to RBS chief executive Hester, Tyrie asked about the causes and implications of the problems, whether job cuts or outsourcing had contributed to them, and if compensation will be paid to customers affected.
Meanwhile, he has also written to Financial Services Authority chairman Lord Turner asking whether the regulator will investigate the causes and consequences of the problems.
Tyrie said: "Basic bank functions are crucial in a modern economy. It is deeply concerning that they appear to have been put at risk again.
"It is also important to know what action the regulators have been taking to ensure proper oversight of banks' computer systems.
"Once we have received responses from the relevant parties, the Treasury Select Committee will decide what further action it may take."
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