Ulster Bank said it has resolved a technical problem which saw overnight payments being delayed

“Some files were delayed through our payment system overnight and these payments have now been made,” a spokeswoman for the bank said in a statement.

“We apologise for this delay and if any customers have been left out of pocket, we will put this right,” she added.

It is understood that impacted customers only included those who were due to get payments .

Customers experienced technical problems for several hours this morning as the bank worked to resolve them. In a tweet earlier today, the company said the issue was with the “online banking service”.

A spokeswoman said the bank did not yet have details of the scale of the problem, but said it was only affecting customers in the Republic of Ireland – Royal Bank of Scotland’s Irish unit.

The problems come a week after a failure in RBS’s online and debit card payments system prevented millions of customers across the United Kingdom from withdrawing cash, paying for goods or using telephone and online banking services.

RBS, which is 82 percent owned by the UK government, was investigated by the Financial Conduct Authority in April when a failure in its technical systems left customers unable to use the bank’s card and online services.

A software upgrade which went wrong also led to similar problems for RBS’s customers in June 2012.