Ireland's leading commercial bank, Allied Irish Banks (AIB), said on Saturday it remained profitable in the first quarter of the year on the back of an improving economy in both Ireland and Britain.

The bank said in its interim management statement that the total number of accounts in arrears in the Irish residential mortgage portfolio declined by 6 percent in the first quarter of 2015 and has reduced by 23 percent since December 2013.

Its total impaired loans reduced by 1.7 billion euros (about 1.9 billion U.S. dollars) in the first quarter to 20.5 billion euros with reductions seen across all its main loan categories, but particularly in the mortgage and commercial investment property sectors, according to AIB.

These reductions were a result of the continued restructuring of the loans of customers in difficulty, repayments of existing loans, an ongoing reduction in the pace of migration to newly impaired loans and the improving economic environment, it said.

The bank said its total assets were broadly stable in the first quarter at 108 billion euros, with customer accounts remaining steady at 64 billion euros.

In March this year, AIB said it garnered a pre-tax profit of 1.1 billion euros last year, compared to a 1.7-billion-euro loss in 2013.

This was the first time the state-owned bank had reported a full year profit since the financial sector here crashed in 2008.

AIB is one of the so-called "big four" commercial banks in Ireland. It offers a full range of personal and corporate banking services.

In February 2009, the Irish government announced a massive rescue package for AIB and its rival Bank of Ireland (BOI), as their bad loan losses soared following the collapse of a domestic real-estate bubble. At present, the government holds 99.8 percent of stake in AIB. (1 euro = 1.12 U.S. dollars)