Saudi Arabian petrochemical stocks led gains on the bourse, which rallied for a seventh session in eight yesterday as earnings expectations buoyed confidence. Most other Gulf markets also rose on an upbeat global backdrop.A fresh report published yesterday said GCC markets were up again in March, gaining 4.6 percent after surging 7.4 percent in February.Gains were led, for the third consecutive month, by Saudi Arabia, which was up 8.39 percent for the month, according to a report from Kuwait Financial Center. (Markaz).The Tadawul All-Share Index (TASI) rose 0.7 percent to its highest level since September 2008. Saudi Basic Industries Corp. rose 1.6 percent, Yanbu National Petrochemical climbed 5.3 percent and National Industrialization (Tasnee) added 2.3 percent.A positive global backdrop, high oil prices and a fresh flood of liquidity into the Saudi market are also supporting local investor confidence. “Investors are shifting into petrochemicals because fundamentals are stronger, dividend yields are attractive and they haven’t risen as much as smaller-cap stocks,” said Muhammad Faisal Potrik, research analyst at Riyad Capital, was quoted as saying in a Reuters report.The total value of shares traded in the first quarter was SR684.71 billion, up 163 percent from a year earlier. Total market capitalization at the end of the first quarter was $410 billion, up 16.7 percent in the prior-year period.Oil rose on Friday to post the biggest quarterly gain since the beginning of 2011 as the growing threat of a disruption to Iranian exports added to supply concerns.World markets were mixed due to tentative economic signals in March, according to the report. The world broad index edged up 1.1 percent in March mainly due to continued strength from Japan.The Nikkei 225 gained another 3.8 percent after surging 10.5 percent in February.