Saudi Arabia's index TASI rose to a 14-week high as investors looked favourably on petrochemical stocks due to rising oil prices.
Bellwether Saudi Basic Industries Corp (SABIC) rose 0.2 percent and Saudi Telecom Co gained 0.4 percent. Yanbu Petrochemical Company was up 1.5 percent. The petrochem index advanced 1 percent.
"Now that general market has won the confidence of investors, you're starting to see more bottom-up buying," said a Riyadh-based trader on terms on anonymity, referring to stock-specific trade. "You will see a lot more of that.
Brent crude for June rose 31 cents to $124.28 a barrel by 1256 GMT.
The benchmark adds 0.6 percent to 6,724 points, its highest close since January 17.
The Gulf's largest utility, Saudi Electricity Co gained 0.4 percent after saying it may change its SR300bn ($80bn) 10-year investment plan as it speeds up delivery of its power projects to meet state infrastructure demands.
UAE markets ended higher after a bout of strong first-quarter earnings boosted investor sentiment and as traders continued to buy into the bourses' possible inclusion in the MSCI index.
Emirates NBD surged 10.9 percent a day after reporting a forecast-beating net profit of AED1.4bn ($381m)
"If we don't have any bad news coming from global markets or oil, markets will continue to be in uptrend," said Sebastian Henin, portfolio manager at TNI National Investment.
"As we come closer to the MSCI announcement, markets should be well oriented," he adds. UAE and Qatar markets are under a second review in June to obtain emerging market status in the MSCI index. Dubai's index DFM ended 1.9 percent higher at 1,666 points, rebounding after three days of losses.
Logistics firm Aramex gained 2.7 percent. It posted first-quarter profit growth of five percent on Tuesday after market close.
Abu Dhabi's index ADI closed 0.6 percent higher at 2,704 points, with banks supporting.
Abu Dhabi Commercial Bank jumped 5.6 percent after its first-quarter net profit more than doubled, helped by lower loan provisions, beating analysts' expectations.
First Gulf Bank rose 2 percent.For all the latest business news from the UAE and Gulf countries, follow us on Twitter and Linkedin, like us on Facebook and subscribe to our YouTube page, which is updated daily.
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