The Tadawul All-Share Index (TASI) rose 0.08 percent to 6,560.25 points — its highest close since July 11. Volumes reached their highest levels for at least two years for a second day, with 476 million shares worth SR8.54 billion changing hands.
"We had the positive message from the General Organization of Social Insurance (GOSI) that they would be increasing their holding in some stocks and this helped the market break out through 6,500," said Haissam Arabi, chief executive and fund manager at Gulfmena Investments.
"Over the next couple of days, the market has to prove this is the new support level but I am positive. The volumes are very healthy and GOSI hasn't stepped in yet."
Zain Saudi Arabia, the most active stock, climbed 4.9 percent, up for a sixth day. the telecoms operator has gained 32.5 percent since Jan. 23.
In Egypt, a five-day rally came to an end as investors held off buying on talk the country's ruling military council could hasten a handover of power to civilians.
National Societe Generale Bank was the biggest drag on the bourse, falling 4.1 percent.
"There's an air of opportunity that seems to be washing over the market during this period. One of the catalysts is the expected proposal of... a handover of power ahead of the scheduled date," said Chamel Fahmy of Pharos Securities.
Mobinil led gainers, up 7.4 percent, with traders citing talk that founder Naguib Sawiris may be trying to raise his family's stake to sell it on to France Telecom.
The main index ended down 0.1 percent at 4,531 points.
In Abu Dhabi, the index snapped an eight-day rally, slipping 0.5 percent to 2,422 points, as Abu Dhabi Commercial Bank and Aldar Properties fell 2.4 and 2.2 percent respectively
In Dubai, National Central Cooling Co. (Tabreed) surged 10.6 percent, its biggest gain in 15 months, as optimism fuelled by fourth-quarter earnings boosted the emirate's stocks.
"There is no news on Tabreed," said one Dubai-based trader.
"The market is good though and people are playing in some stocks. Everyone is expecting good things from the results."
The Dubai exchange advanced 0.3 percent, reversing Sunday's decline of the same amount.
Banks helped Qatar's index to rise 0.6 percent.
The biggest climber was Masraf Al-Rayan, which ended 2.9 percent higher. On Sunday, the lender reported a 16.3 percent rise in annual earnings.
"We believe the strong thrust in profitability has come on... expansion in financing activity and improved margins," Digvijay Tanwar of Global Investment House said in a note.
Doha Bank and Commercial Bank of Qatar gained 0.7 and 1.5 percent respectively.
In Kuwait, the exchange advanced 0.1 percent, the fifth session in six that it has ended higher ahead of a Feb. 2 parliamentary election.
"Until we see the outcome of the election, Kuwait is very much on hold," Arabi said.
