Dubai Financial Market cut the cap it imposes on daily stock movements to 10 percent from 15 percent on Sunday to limit the impact of global market volatility that has seen bourses around the world plummet.
The decision was taken "in view of the exceptional global financial circumstances and the fluctuations currently witnessed in international markets," the bourse said in a statement.
The move was temporary, the bourse said, without indicating how long it would last.
Meanwhile, Dubai's main index fell more than 6 percent in early trade, led by real estate and banking shares.
Emaar Properties dived 10 percent, while construction firm Arabtec dropped 9.9 percent.
Union Properties also plunged 9.9 percent. Dubai Islamic Bank and Dubai Investments declined 5 percent and 9.1 percent respectively.
The benchmark, which on Thursday closed at 3-1/2-year lows and has lost almost 50 percent since the beginning of the year, lost 6.02 percent to 3,004 points.
In Abu Dhabi, real estate and bank stocks are also the hardest hit, with Aldar Properties and Sorouh Real Estate declining 8.6 percent and 8.7 percent respectively.
National Bank of Abu Dhabi and Abu Dhabi Commercial Bank dropped 4.8 percent and 6.5 percent respectively.
Etisalat declined 8.7 percent. The index which has also lost nearly 50 percent since the beginning of the year, dropped 4.09 percent to 3,076 points. -Reuters