RIYADH: Saudi Arabia’s main index declined in the first session of the week, amid cautious investor sentiment ahead of domestic inflation data and the Federal Reserve’s interest rate announcement. The Tadawul All Share Index shed 2.18 percent to end Sunday at 11,572, while the parallel market Nomu slipped 1.62 percent at 20,585. Saudi oil giant Aramco ended the session with 0.68 percent decline, while Rabigh Refining and Petrochemical Co. fell 4.27 percent. Almarai Co. dropped 0.75 percent, after announcing the full redemption of its SR1.6 billion ($426 million) sukuk on Sept. 16. The Kingdom’s largest valued bank Al Rajhi slipped 2.17 percent, while Alinma Bank edged down 1.36 percent. The Saudi National Bank, which is the Kingdom’s largest lender, decreased 2.45 percent. Saudi British Bank declined 1.99 percent, after completing a SR1.2 billion deal to trade certain lines of business between HSBC Saudi Arabia and Alawwal Invest Co. ACWA Power Co. lost 7.3 percent to lead the fallers, while Walaa Cooperative Insurance Co. gained 9.78 percent to lead the gainers after its shareholders approved its merger with rival insurer SABB Takaful.