KBC Bank Ireland has today reported a loss of €177m for 2010 after tax and impairment costs.
Loan impairment costs rose to €525m.
The institution revealed an overall loan portfolio stood at €17.2bn by the end of the year compared to €18bn in 2009.
The bank says some of its customers are having difficulty but the majority are able to repay their loans.
"We are committed to working with those customers in difficulties," said KBC Bank Ireland chief executive John Reynolds.
"We also wish to do more business with viable borrowers and to provide a first class service to all our customers.
'We remain optimistic in the medium term about the country's capacity to recover positive momentum."
Earlier this week, the bank announced that it is to increase the interest charged on its fixed-rate mortgages by up to 0.7%.