Most Gulf Arab markets fell on Thursday as a sharp decline in oil prices, falling global markets and rising tensions in the Middle East dampened sentiment among investors.

United Arab Emirates shares were the hardest hit as real estate stocks weighed on Dubai's index, reversing gains from earlier in the week as investors cashed out following global market declines on a worsening economic outlook.

Kuwait's bourse extended losses into a second day after Global Investment House, the country's biggest investment bank, said it had defaulted on most of its debt.

Global slumped 6.58 percent, adding to almost two weeks of declines as the crisis of investment firms hit by the global credit crunch widened in the Gulf Arab state.

'Global has been acting like this because of speculation it will go bust,' said Jasem al-Zeraei, supervisor of brokerage at National Bank of Kuwait.

'There is negative outlook for 2009, the oil price, Gaza and now Lebanon being pulled into the mix,' Zeraei said.

Oil prices closed 12 percent down at about $42 on Wednesday, although they edged slightly higher on Thursday after Israel fired artillery at Lebanon in response to rockets fired at northern Israel.

World stocks fell on Thursday after bleak data and poor corporate earnings stoked gloom about the economic outlook.

Markets in Oman, Bahrain and Abu Dhabi all closed down. Qatar's main index bucked the downward trend as investors bought after three days of declines and news of a merger between Gulf Warehousing Company, the Qatari unit of Kuwaiti logistics provider Agility boosted the market.

Saudi Arabia's bourse is closed on Thursday. The Dubai measure closed 2.39 percent down to 1,728 points. Emaar Properties shed 7.28 percent and Dubai Financial Market slipped 5.63 percent.

'Markets in the United States, Europe all went down and because of this we are also down,' said Shawkut Raslan, head of brokerage at Prime Emirates.

The Abu Dhabi index extended losses into a second session, sliding 0.54 percent to 2,527 points.

National Bank of Abu Dhabi continued to fall since its chairman resigned on Wednesday, slipping 1.59 percent. First Gulf Bank closed 3.83 percent lower.

The Kuwait index slipped 0.76 percent to 7,371 points. Investment Dar closed 6.17 percent lower. The Oman measure closed lower for the third time in four sessions. It fell 0.63 percent to 5,427 points.

Bank Muscat shed 1.24 percent and National Bank of Oman 0.55 percent. The Bahrain benchmark closed 0.69 percent lower at 1,780 points. Ithmaar Bank plunged 8.51 percent.

The Qatar benchmark reversed recent losses ending 2.21 percent up at 6,432 points. Gulf Warehousing Co closed 8.6 percent up. Commercial Bank of Qatar ended 3.8 percent higher.-Reuters