Ratings agency Standard & Poor’s (S&P) has downgraded the credit rating of Australia’s big four banks, marking a fall from AA to AA-.


Also announced was a downgrade of investment bank Macquarie Group, which has fallen from A- to BBB+.


The agency announced the two rating drop for Macquarie on the grounds of increased vulnerability from its international assets, while the major four banks have controlled their vulnerability to major international downward trends.


The ratings drop come as a result of the rating agency announcing changes to its assessment criteria announced earlier this month.


The drop comes only a matter of days after fellow ratings agency Fitch upgraded Australia’s credit rating to AAA, marking the first time the country has received top credit ratings from all three major agencies.