Saudi stock benchmark Tadawul All Share Index advanced 0.98 percent to 6,418.8, the highest level since June 21, at close Monday, leading gains in Gulf markets, as oil advanced and amid optimism the global economic recovery isn't faltering. Oil prices surged Monday. New York's main contract, light, sweet crude for October delivery, rose $1.20 to $74.86 per barrel. London's Brent North Sea crude edged up $1.11 to $79.32. “Positive sentiment from international markets continues to cheer investors,” before the US Federal Reserve's policy meeting tomorrow, said Amro Halwani, a trader at Shuaa Capital PSC in Riyadh. “The rise in oil is pushing petrochemical prices higher and higher.” SABIC advanced to SR90.25, the highest level since July 11. Al Rajhi Bank increased 0.6 percent to SR78.50, the highest in almost one week. In Dubai, the DFM General Index rose for a fourth day, climbing 0.5 percent after earlier retreating as much as 1.1 percent. The gauge advanced 14 percent so far this month. “Medium-term and long-term investors believe there is more upside potential,” said Hassan El Salah, deputy head of institutional equities at Al Ramz Securities LLC, an Abu Dhabi- based brokerage. Qatar's QE Index and Bahrain's measure increased 0.1 percent. The Kuwait Stock Exchange Index and Oman's MSM30 Index rose 0.4 percent each. Abu Dhabi's ADX General Index was little changed.