MIDEAST STOCKS-Region hit by global sell-off, Saudi-Iran tensions

* Saudi stocks sold off in last hour of trade

* Savola slides because of exposure to Iran

* FX forwards, CDS show foreign investor jitters

* UAE could lose out on post-sanctions Iran boom

* Egypt erases previous day's gains

By Celine Aswad

DUBAI, Jan 4 (Reuters) - Most Middle East stock markets tumbled on Monday in a global sell-off triggered by China, while growing tensions between Saudi Arabia and Iran added to the gloom.

Chinese stocks slumped by 7 percent after weak manufacturing data, causing emerging markets in general to suffer their biggest fall in four months.

"The broad market sell-off is part of the general weakness in global equity markets," said Muhammad Shabbir, head of equity funds at Dubai-based Rasmala Investment Bank.

The lack of a catalyst that would support a market rally in the Gulf leaves the region vulnerable to volatile trade, he added. In past years, the region outperformed emerging markets because of its strong budget and current account surpluses, but most of those surpluses have now been erased by low oil prices.

"While rising geopolitical tension makes headlines and weighs on sentiment, weakness in oil and worries about Chinese demand remain the primary drivers of GCC (Gulf Cooperation Council) stock markets," said Akber Khan, director of asset management at Doha's Al Rayan Investment.

Saudi Arabia cut diplomatic ties with Iran on Sunday in response to the storming of its embassy in Tehran. The attack came after the Saudis executed a leading Shi'ite cleric, Nimr al-Nimir, on terrorism charges, infuriating predominately Shi'ite Iran.

Local investors have largely ignored geopolitical tensions in the Gulf for some years. But the latest events marked an escalation, and foreign investors in particular may become more cautious about the region.

Reflecting that caution, the Saudi riyal fell to near a 16-year low against the U.S. dollar in the forward foreign exchange market on Monday. Meanwhile, the cost of insuring Saudi sovereign debt against default rose to multi-year highs .

Riyadh's equities benchmark faced a heavy sell-off in the last hour of trade as investors dumped stocks across the board. The index sank 2.4 percent.

Savola, one of the few Saudi companies with a presence in Iran, fell 3.2 percent. The food conglomerate has factories in Tehran; Iran provided 11 percent of its revenue in the third quarter of 2015 and the company's revenues from Iran totalled 2 billion riyals ($534 million) in the first nine months of 2015, its financial statements showed.

Islamic lender Alinma retreated 3.7 percent after rising in early trade. Health insurer Bupa Arabia, usually a favourite of foreign investors, plunged 9.6 percent.