Former National Australia Bank executive Mike Soden has resigned his $2.5 million a year position as chief executive of the Bank of Ireland after he was caught accessing an escort agency website from his office computer.In a statement issued on Saturday, Soden admitted using his PC to access "Internet sites that contain content that infringed [Bank of Ireland's] policy on these matters. The content accessed was not illegal but did contain links to material of an adult nature," the statement says.Checks by BOI's computer staff last Monday revealed that Soden had accessed the escort agency site several times in early April, according the Dublin-based Sunday Business Post.The Observer newspaper quotes a bank source as saying it was not clear if this was in Ireland or if he used the services of the agency.This was the first time that bank staff had used computer software that can check on employees' internet usage, according to The Post.Last year, BOI signed an $850 million contract to outsource its information technology to Hewlett Packard for seven years. The deal affected some 500 of the bank's IT staff, who staged a 24-hour strike in August before independent arbitrators settled concerns over their job security, redeployment and protection of pension rights.Soden says he had insisted on the highest standards of integrity and behaviour as chief executive and that his actions were inappropriate and would cause embarrassment to BOI and its staff."For this reason and because I believe that leaders of organisations should be measured by the highest standards, I have made this decision," he says.BOI's internal policy bans employees from accessing internet sites unrelated to the bank's business and adult sites are specifically proscribed.Protests from Irish women's groups and the Roman Catholic Church earlier this year forced BOI to pull out of deal in the UK to finance the purchase of 45 adult magazines from Daily Express publisher Richard Desmond.Born in Dublin, Soden's appointment as BOI's chief executive in 2002 marked his return home after an international banking career that included stints as chief executive of Citicorp Investment Bank in Canada, and Security Pacific Hoare Govett in London.In 1994, he joined NAB's London wholesale banking operation and moved to Melbourne to run global wholesale banking, then global retail banking, before leaving in 2001 for BOI.Governor of the Bank of Ireland, Laurence Crowley said it had accepted Soden's resignation with regret. "Mike has made an enormous contribution to the Group since he took up the position of Group chief executive in March 2002," he said.Soden is expected to also resign his directorship of Britain's Post Office, to which he was appointed only two weeks ago as part of a joint venture to distribute BOI's financial services products through post offices.