S&P cuts Australia's 'big four' banks' credit outlook to negative

Credit outlook for CBA, Westpac, ANZ, and NAB were all cut
– Ratings/Outlook were cut from AA-/Stable to AA-/Negative
The reasoning for downgrade by S&P is that it reflects the  earlier, which means a "slightly reduced financial capacity to provide timely financial support to the systemically important financial institutions, if needed".