Ulster Bank has denied that customers in Northern Ireland are being put to the back of a queue when it comes to sorting out the aftermath of a computer glitch which has left a backlog of uncompleted transactions
The bank has also promised that customer's credit ratings would not be affected by the glitch, stretching into its second week.
While the problems at parent bank RBS and sister institution NatWest are all but rectified it could be Monday before the Ulster Bank backlog of transactions and payments can be cleared.
The group says 99% of RBS and NatWest balances and payments are now up to date, but problems persist for Ulster Bank's 1.9m customers throughout Ireland.
The underlying glitch was fixed on Friday, but the group is now working through the backlog.
The problem emerged last Wednesday and has lead to wages and benefits not being paid in, direct debits not going in or out and not being able to view transactions online.
About 27,000 social security agency customers have been affected by the problems.
Some Ulster Bank cards and ATMs were not working last week, while others experienced problems lodging cheques.
Computers and other electronic equipment in many branches were not operational and many branches across Northern Ireland remained open until 7pm to deal with customer queries.
Amid accusations that customers in Northern Ireland were being put to the back of the queue as the situation at sister banks was resolved, a spokesman for Ulster Bank said that the problem had to be dealt with in the same timeframe that it happened.
"RBS Group have to deal with the systems issues in the sequence they occurred - RBS, NatWest and then Ulster Bank - to ensure that we deal with them effectively," he said. "To try and change the sequence could cause more issues than it would resolve."
The spokesman also moved to reassure customers that they would not be left out of cash nor would credit ratings be affected.
"To help all those customers and businesses impacted by this issue we are working with the Payments Council and IPSO to agree how other banks and building societies will help to ensure customers are not out of pocket."
Responding to criticism from some customers that Ulster Bank representatives had been slow to give public explanations for what happened, he said: "Given that this is an RBS Group IT issue, a very senior RBS spokesperson was also available for comment last Sunday evening. Our top priority is to clear the backlog of payments and we are working around the clock to do this."
The bank has also denied media reports that the fault was caused by a technician in India.
While RBS would not comment on the reports head of branch banking at Ulster Bank Jim Ryan said the technical problems were confined to the UK.
"The error is an error on the island of the UK where our technical infrastructure resides," he said.
Ulster Bank said it has had a busy couple of days.
"Footfall through our branches yesterday was approximately 11,000 across Northern Ireland and we handled 19,000 calls through our call centre."
Who is Jim Brown?
By Laura Noonan
An affable Kiwi, Ulster Bank chief executive Jim Brown is hard to miss in the flesh. But over the last week and a half he's become the invisible man of Ulster Bank's IT meltdown, leaving it to divisional heads to update the media and customers.
Some say he's simply 'shy', and point to the media profile he's kept since he took the top job in April 2011. In over a year at the top of Ireland's third biggest bank, he's given just one interview.
Brown hasn't been totally absent over the crisis - he put in an appearance on conference calls with other banks, as Ulster Bank asked them what they could do for customers afflicted by the IT meltdown.
Suffering is 'unacceptable'
By Vicky Shaw
The head of a powerful Commons committee has demanded answers from RBS bosses over the IT meltdown that left thousands of Ulster Bank customers in hardship.
Treasury select committee chairman Andrew Tyrie said that he has written to RBS chief executive Stephen Hester (right) and FSA chairman Lord Turner to find out exactly what went wrong.
Mr Tyrie said further action will be decided when the responses are received.
He added: "It is clearly unacceptable that so many people have suffered, and continue to do so, as a result of what looks to have been a major IT failure."
Clearing the backlog
Ulster Bank is working through a backlog to ensure all delayed transactions go through in the right order.
This means that if you carried out a number of transactions in the past week, the first to go through will be the oldest one.
Brian Honan of BH Consulting, which specialises in IT security, said it was taking a long time because millions of transactions had been affected by the "glitch".
"It will be an automated job in as much as possible and they will be doing it in sequence," he explained.
But Mr Honan said he expects people to query transactions and fees for months after the backlog is cleared.