RBS and NatWest customers were unable to make card and online payments for several hours on Monday as the strain of Cyber Monday appeared too much for the bank.
Hundreds of customers took to Twitter and online forums to vent their anger as they were unable to pay for goods online or in store, leaving many unable to make purchases.
RBS Group, which owns the RBS and NatWest high-street banking brands, acknowledged the issues and apologised, but did explain what caused the issue.
“The systems issues that affected our customers last night have now been resolved and all our services are now back working normally. We would like to apologise to our customers. If anyone has been left out of pocket as a result of these systems problems, we will put this right,” it said.
It also issued the same statement over Twitter:
We would like to apologise to our customers. If anyone has been left out of pocket as a result of these problems, we will put this right.— RBS Group (@RBSGroup) December 3, 2013
V3 contacted RBS Group for more information about the cause of the latest issue but had received no reply at the time of publication.
The CEO of RBS, Ross McEwan, said it was "unacceptable" the issues had affected so many customers and that it would striving to improve the situation by improving its IT systems.
"For decades, RBS failed to invest properly in its systems. We need to put our customers' needs at the centre of all we do. It will take time, but we are investing heavily in building IT systems our customers can rely on," he said.
"I'm sorry for the inconvenience we caused our customers. We know we have to do better. I will be outlining plans in the New Year for making RBS the bank that our customers and the UK need it to be. This will include an outline of where we intend to invest for the future."
The incident brought back memories of a similar outage that occurred in 2012 when a botched software update caused widespread issues including failed salary payments and bill transactions. The incident cost the firm £175m in compensation payments.
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