Share prices in the energy-rich Gulf states fell sharply on Thursday as oil dived to an 11-year low and China triggered a global markets rout.
The gloomy economic indicators and tensions between regional heavyweights Saudi Arabia and Iran combined to dent investor confidence, leading to a massive sell-off that sent prices crashing.
All seven Gulf bourses ended the last trading day of the Muslim week in negative territory, with the slide led by the Saudi market, the region's largest.
"Several negative factors combined to dampen investor confidence in the Gulf bourses, leading them to dump shares," said Mohammad Zidan, chief market strategist at Kuwait's Orbex Brokerage.
"Oil prices continued to fall, with no bottom in sight. China's economic woes appear to be deeper than earlier believed and Saudi-Iran tensions just added insult to injury," Zidan told AFP.
The Saudi Tadawul All-Shares Index dipped 4.5 per cent to finish on 6,225.22 points, a three-year low.
All its 15 sectors dropped, with banking shedding 4.6 per cent and petrochemicals 3.3 per cent.
The Dubai Financial Market Index dropped 3.4 per cent to fall below the key 3,000-point mark for the first time this year. It closed on 2,966.3 points. Leader Emaar properties sank 5.4 per cent and most stocks ended down.
Its sister market in Abu Dhabi dipped 3.2 per cent to end the day on 4,135 points.
The Qatar Exchange, the region's second largest, dropped 3 per cent, falling below the 9,800 mark, with losses across all sectors.
The normally dormant Kuwait Stock Exchange followed suit, losing 1.6 per cent to trade at levels last seen 11 years ago.
The small Oman and Bahrain bourses lost 0.5 per cent and 0.7 per cent respectively.
All Gulf stock exchanges ended 2015 in negative territory, led by Saudi Arabia, after the sharp decline in oil prices.
Riyadh broke off diplomatic ties with Iran on Sunday after protesters set fire to its Tehran embassy and a consulate in second city Mashhad.
Oil prices plunged close to $33 a barrel on Thursday, as crude extended losses on rising US energy stockpiles and China's weakening currency.
Beijing suspended trading at its two bourses after losses reached seven per cent due to a poor economic outlook in the world's second largest economy.
European stock markets tumbled at the start of trading Thursday following heavy sell-offs across Asia.