RIYADH: Shares in Saudi giants Aramco and Saudi Basic Industries Corp. advanced on Tuesday after credit rating agency Fitch upgraded its outlook for both firms. Chemical firm SABIC’s stock gained 1 percent to SR122 ($33) as of 11:00 a.m. Saudi time, and it"s parent Aramco edged 0.12 percent higher to SR43, implying a market cap of SR8.6 trillion. Fitch Ratings had revised the long-term foreign-currency issuer default rating of SABIC to positive from stable and affirmed its A rating, following a similar upgrade on its majority parent Aramco. The outlook for the state-owned oil giant was also revised from stable to positive on the back of improvements in the country’s sovereign balance sheet, thanks to higher oil revenues. “SABIC’s rating is aligned with that of its parent Saudi Aramco, reflecting the strength of the ties between the two companies in accordance with Fitch’s Parent and Subsidiary Linkage Rating Criteria,” Fitch said. “SABIC stands out among its ‘A’ rating category peers as it is a commoditized chemical company,” it added. The only other Fitch A-rated chemical company is German multinational BASF SE.