Abu Dhabi's bourse crossed the 4,000 mark for the first time in five years as it played catch up to gains on neighbouring Dubai market, which extended a rally driven by real estate stocks.
Abu Dhabi's index climbed 0.3 percent to close at 4,001 points, its highest close since September 2008.
The market is up 52.1 percent year-to-date, while Dubai's index has rallied 91.1 percent.
Shares that were lagging the benchmark performance led gains. National Bank of Abu Dhabi and Abu Dhabi National Energy (TAQA) advanced 1.6 and 3.8 percent respectively.
"Abu Dhabi is just seeing a catch-up move, I don't think it will trigger a major change in sentiment," said Sebastien Henin, portfolio manager at The National Investor.
Dubai's measure meanwhile rose 1.5 percent to finish at 3,100 points, a new five-year high.
Real estate stocks rallied, buoyed by a sharp recovery in the sector's prices and rent.
Emaar Properties and Deyaar Development jumped 3.4 and 5.3 percent respectively.
"Investors are more comfortable to invest in Dubai real estate, which reflects the economic recovery. It shows a vote of confidence, which is lacking in the Abu Dhabi real estate," Henin said.
Elsewhere, Saudi Arabia's index ticked up 0.2 percent to 8,334 points, while Egypt's benchmark index was little changed at 6,484 points.
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