...State Support Probability Extremely High: Riyad Bank's (RB) Issuer Default Ratings (IDRs) are driven by an extremely high probability of support from the Saudi Arabian authorities, if required. This reflects a strong ability and long history of support in Saudi Arabia, as well as the bank's D-SIB status. RB's Viability Rating (VR) reflects the bank's solid capital ratios, strong commercial franchise with leading market shares in some business lines, solid core earnings generation and diversification, and sound asset quality. It also reflects high concentration risks in assets and liabilities and a weakening operating environment. Weakening Operating Environment: Fitch Ratings believes that the Saudi Arabian banking sector is facing a tougher operating environment, mainly due to the impact of lower oil prices on government spending and the filter-down effect this has on the rest of the economy. Strong Capital Ratios: Capital ratios are strong and commensurate with RB's risk profile. The...