Background: The chairman of AIB, Mr Dermot Gleeson SC, has pledged his full support for the bank's embattled chief executive, Mr Michael Buckley.

In a letter to the chairman of the Joint Oireachtas Committee on Finance and the Public Services - in which he defended Mr Buckley's refusal to attend the committee's hearings yesterday - Mr Gleeson said the chief executive "has my full support and the support of the board".

There have been calls for Mr Buckley to resign over the past three weeks as the bank has been hit by a succession of scandals.

The Oireachtas committee yesterday held hearings into the issues, which included the overcharging of foreign exchange customers and the use by senior executives of investment vehicles managed by AIB's investment arm, AIB Investment Managers (AIBIM), between 1989 and 1996, which were in breach of tax laws.

Mr Buckley has refused to meet the committee until an independent investigation into the foreign exchange overcharging was complete. Mr Lauri McDonald, former Comptroller & Auditor General, is leading the inquiry.

Mr Buckley's refusal predated the emergence on Friday of the offshore investment controversy.

The chairman defended Mr Buckley in his letter, saying that "one of the key objectives which Michael Buckley has been working on since he became chief executive in mid 2001 has been to make whatever changes are needed in the culture and organisation practices of AIB".

He said Mr Buckley had his and the board's support for "progressing this work into the future".

Mr Buckley, a former civil servant, joined AIB in 1992 as head of AIB Investment Banking, which included AIB Investment Services, the forerunner of AIBIM. He was promoted to head of AIB Capital Markets, the parent of AIB Investment Banking, in 1996.