[LONDON] HSBC Holdings Plc said most of the 275,000 payments from UK business customers it failed to process on Friday were completed by the end of the day after a software problem held up transactions before a long weekend.

The system breakdown resulted from an information- technology glitch and isn't related to hacking or criminal activity, according to a person with knowledge of the matter, who asked not to be identified because an internal investigation by the bank is private. The failure delayed transactions on the final business day of the month, when many British salaries are paid.

"Over 99 per cent of payments that were delayed today have now been processed, with the remaining to be credited overnight," HSBC, Europe's largest bank, said in an e-mailed statement late on Friday. "HSBC apologises again for the inconvenience caused."

The problem was with the BACS system, which processes electronic payments, the bank said in an earlier Twitter post. HSBC hasn't elaborated on the exact cause of the problem.

Monday, Aug 31, is a public holiday in Britain, and the glitch had raised the prospect that many people would have been left without pay before the long weekend that marks the end of the summer.

"We are committed to ensuring that no one loses out as a result of today's unacceptable problems," HSBC said. "We will work with our customers and the other banks, including providing compensation where appropriate." The Bank of England said earlier it's in contact with HSBC regarding the problem and will be working with the lender to resolve the issue.

British banks have faced a string of costly information- technology failures in recent years, with some attributed to obsolete software and others to malicious activity by hackers.

Royal Bank of Scotland Group Plc suffered a payments glitch in June, affecting 600,000 credit and direct-debit transactions, only seven months after it was fined 56 million pounds (S$121 million) by the UK's Financial Conduct Authority for a computer failure that left millions of customers without access to their accounts for weeks.

"I will be writing to the chief executive of HSBC to obtain an assurance that no customers will lose out from these failures and to ask what is going to be done to prevent a repetition," Conservative party lawmaker and Treasury Committee Chair Andrew Tyrie said in an e-mail. "It is increasingly clear that most, if not all, of these banks' IT payments systems need a good deal of investment."

If customers have not received the delayed payments by Saturday morning, they should speak with their bank, HSBC said in the statement as it apologised to customers.

BLOOMBERG