...- On April 8, 2020, we revised the outlook on our long-term issuer credit rating on Australia to negative from stable to reflect a substantial deterioration in the sovereign's fiscal headroom at the '###' rating level. - A lower rating on the sovereign would reflect slightly reduced financial capacity to provide timely financial support to NAB and other systemically important institutions, if needed. - We are revising our outlook on NAB to negative from stable, and affirming our '##-' long-term and 'A-1+' short-term ratings on the bank. - The negative outlook reflects a one-in-three likelihood that we will lower our long-term rating on NAB in the next two years. In our base case, we expect that despite a significant fall in interest and fee income, NAB's earnings in the next two years will remain sufficient to absorb the increase in credit losses due to the COVID-19 outbreak and containment measures....