Abu Dhabi's bourse climbed to a new 58-month high, backed by a bullish outlook on banks, while Dubai extended gains after a choppy session.
Shares in First Gulf Bank jumped 4.9 percent, National Bank of Abu Dhabi rose 1.9 percent and Invest Bank gained 5.7 percent.
Many of the emirate's banks have reported strong earnings growth in the second quarter, with some beating analysts' forecasts, confirming they are benefiting from an economic recovery.
"People are still positive and expecting more growth in results for the coming quarters," said Nabil Al Rantisi, managing director at MENA Corp brokerage. "Participation has picked up from all sides, retail and institutional"
Abu Dhabi's measure rose 2.0 percent to close at 3,923 points, its highest since September 2008.
"The index is searching for a major top - then a correction will start, which will last for at least three to four months," said Feras Al Zghaibi, financial markets strategist at MENA Corp. The market could pull back by 400 to 600 points at a minimum, and any break below major support of 3,834 points would trigger major stop-loss orders on short-term charts, he added.
In Dubai, the index climbed 0.2 percent to close at 2,595 points, a 56-month high.
District cooling firm Tabreed gained 0.5 percent after it reported a 37 percent increase in second-quarter net profit.
In Doha, Barwa Real Estate fell 2.9 percent to close at 25.50 riyals, though it partially recovers from a two-month low of 24.98 riyals hit at the opening after the developer reported a slump in first-half earnings.
The index ended near-flat at 9,707 points.
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