Saudi Basic Industries Corp. (SABIC), the world's biggest petrochemicals manufacturer by sales, surged the most in almost five years after first-quarter profit beat estimates. The shares soared 9.8 percent, the most since May 2010, to SR95.75 at 12:22 p.m. in Riyadh. The stock was the exchange's biggest gainer and helped lift the Tadawul All Share Index 3.4 percent. SABIC reported a 39 percent decline in first-quarter profit to SR3.93 billion ($1.05 billion) as average sales prices dropped following a slump in global crude prices. The mean estimate of seven analysts was for a profit of SR3.28 billion, according to data compiled by Bloomberg. SABIC plans to cut costs and is well positioned to deliver sustainable growth, Acting Chief Executive Officer Yousef Al-Benyan told reporters in Riyadh on Sunday. Mosaed Al-Ohali, the company's executive vice president for polymers, will become chief financial officer from May 1, Al-Benyan said. SABIC, which is 70 percent state-owned, attributed the profit fall to lower average sales prices. The company's results are closely tied to oil prices and global economic growth because its products - plastics, fertilizers and metals - are used extensively in construction, agriculture, industry and the manufacturing of consumer goods. Lower oil prices adversely affected SABIC's earnings in the final quarter of 2014 and the company warned in January that 2015 earnings would be unpredictable, with challenges especially prominent in the early part of the year. — SG/Agencies