A long-term, local staffer will run the British banking operations of National Australia Bank for the first time in the bank's quarter century of direct investment in the UK.David Thorburn, who joined Clydesdale Bank as a management trainee in 1978, will take over as chief executive of NAB's UK business from July 2011.Lynne Peacock, who joined NAB from the Woolwich Building Society and Barclays in 2003, will leave the bank at the same time, after eight years with the group and seven years as CEO.The bank also announced the retirement yesterday, effective from August 2011, of Michael Ullmer as deputy chief executive of the NAB group. NAB will not fill this role.David Thorburn has not spent his entire banking career with Clydesdale, having spent a decade in the 1980s and 1990s working with TSB in Scotland. He returned to Clydesdale in 1993, eventually running business banking for the group.He became chief operating officer of the bank in 2002.Prior to the appointment of Lynne Peacock as CEO in the UK Clydesdale was a training ground for promising Australian executives of NAB. Frank Cicutto, later group CEO of NAB and Stuart Grimshaw, who later crossed to Commonwealth Bank, were among the Australians rotated through the CEO post in Glasgow.The planned management changes at NAB in the UK provided yet another opportunity for market and media speculation over the perennial question of whether NAB is a buyer or seller of banking assets in the UK.Lynne Peacock's series of media interviews on Tuesday, UK time, provided no firm clues.Some media outlets, such as Dow Jones, preferred a quotes emphasis on the importance of organic growth. Others, such as Reuters, preferred a quotes emphasis on the need for NAB to consider acquisitions.