In an announcement to the ASX, NAB said an exit from the UK Clydesdale business by the end of the calendar year is a "priority".
"As a result, NAB is today providing the market with an update on the business, the UK market backdrop and introducing new Clydesdale chief executive officer David Duffy," the statement said.
The proposed exit will see a demerger of between 70 and 80 per cent of Clydesdale to existing NAB shareholders, as well as an IPO of approximately 20 to 30 per cent of the bank to institutional investors.
The primary listing will be on the London stock exchange, and as well as a listing of a CHESS depositary interest on the ASX.
An analysis published by Morningstar yesterday noted new NAB chief executive Andrew Thorburn is "wasting no time" in dealing with the legacy issue of Clydesdale.
"NAB has not made a final decision to sell Clydesdale, but the stars seem to be finally aligning, supporting the eventual exit from the UK," Morningstar said.
"There is no guarantee the separation will occur as it is complex and requires a wide range of approvals, including regulatory and shareholder approvals.
"But this is the best exit opportunity NAB has had for several years and, if successful, will enable management to refocus on the far more profitable Australian and New Zealand operations," Morningstar said.