National Australia Bank has increased its provisions for bad debts by $A250 million due to worsening economic conditions.
The bank said the rise in provisions is due to a weak global economy, particularly a struggling subsidiary in Britain.
NAB's provisions related to a negative economic cycle now total $A320 million.
Chief executive Cameron Clyne says the move is prudent given the poor economic conditions in Britain and slowing economy in Australia.
The ABC reports NAB reduced its forecast in October for 2013 Australian GDP growth to 2.5% from 3.3% in July.
Excluding the increase in bad debt provisions, the bank said cash earnings for the fourth quarter were around $A1.4 billion - roughly in line with the previous quarter.
NAB shares were down 3% to $A26.14 by 2:34pm (AEDT) on Friday.