The move would lead to the listing of Yorkshire and Clydesdale banks on the London Stock Exchange.
NAB’s 2014 full-year cash earnings fell almost 10% to $5.18 billion, largely due to provisions relating to a misconduct over insurance policies.
Yorkshire and Clydesdale, which have 2.7million customers and 330 branches, have also taken a big hit on PPI and swaps mis-selling, forcing it to put aside more than £1.2bn in compensation.
Andrew Thorburn, chief executive of NAB, said:
"In relation to exiting UK banking this means we are now examining a broader range of options including those provided by public markets.
"We have an intention to exit the UK, we think there's an opportunity now that probably wasn't there before. What we are signalling is that's our intent, it is an absolute priority."
The group has axed 1,400 jobs as part of restructuring and quarantined £5.6 billion worth of troubled commercial real estate loans.
