Banking customers across the UK have reported having their cards declined in shops, with some unable to withdraw cash from ATM machines, according to news outlets.
The banks affected are all reported to be be members of the Lloyds Banking Group and include Halifax, Bank of Scotland and TSB branches as well as those of Lloyds itself, according to the BBC.
TSB CEO Paul Pester said on Twitter that the bank is trying to resolve the problems.
"My apologies to TSB customers having problems with their cards. I'm working hard with my team now to try to fix the problems," he said.
At the time of writing no further information was available on the banks' websites.
TSB bank is currently being transferred to a new owner following a 2009 ruling by the EC.
Meanwhile Lloyds customer service said the problem affects debit cards and not credit cards, according to Sky News.
The cause of the current glitch is unknown, but many high street banks have been hit by IT failures recently.
Lloyds TSB and Halifax customers have experienced access problems before, such as in June 2012 when they found themselves locked out of online banking accounts.
Possibly the worst of these incidents was the prolonged outage suffered by RBS Group just before that, which affected NatWest, Ulster Bank and Royal Bank of Scotland customers. The same group experienced a similar problem last month on Cyber Monday.
In November 2013 the bank of England said that several UK banks had been hit by cyber attacks over the previous six months.
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