Irish Life and Permanent's (IL&P) treasurer Michael Torpey is to become head of banking with the National Treasury Management Agency (NTMA).
The financial group today announced Mr Torpey would resign from the group to take up the position, with his successor to be appointed within weeks.
Mr Torpey was previously finance director of Ulster Bank and First Active, a role held between 2000 and 2008. Before that, he was group treasurer of Irish Permanent, which became Irish Life and Permanent plc in 1999.
IL&P chief executive Kevin Murphy said the group was disappointed to see Mr Torpey leave, but "fully appreciated" the significance of the NTMA role.