* Saudi hit by prospect of lower oil prices
* Dubai climbs on hopes for more Iran business
* Some Gulf transport, services firms rise on Iran factor
* Dubai's DAMAC up as it considers London property project
* Egypt sinks after poor March corporate survey
By Andrew Torchia
DUBAI, April 5 (Reuters) - Gulf stock markets reacted very differently on Sunday to Iran's nuclear deal with world powers, as Dubai rose on hopes for new Iranian business while Saudi Arabia fell on fears of lower oil prices. Egypt continued sliding after poor economic data.
If confirmed in a final agreement by a June 30 deadline, the nuclear deal - assuming it is received positively by major Gulf Arab governments - could reduce geopolitical tensions in the area, encouraging more foreign portfolio investment throughout the region.
But Saudi investors focused instead on the fact that lifting international sanctions on Iran would allow more Iranian oil onto the market, potentially pushing down crude prices and hurting profit margins of the petrochemical producers which are heavily weighted in the Saudi bourse. Brent oil plunged nearly 4.0 percent on Thursday in an initial reaction to the deal.
The main Saudi stock index fell 1.7 percent on Sunday with Saudi Basic Industries Corp, the biggest petrochemical maker, losing 1.5 percent.
Among outperforming stocks were Saudi Public Transport Co , which rose 0.6 percent in active trade after calling an annual general meeting for Monday to approve, among other things, a 7.5 percent dividend payment.
BENEFITS
By contrast, Dubai's open and trade-oriented economy would probably benefit from the lifting of sanctions on Tehran, as the emirate became a jumping-off point for foreign companies and traders going back into Iran.
The main Dubai stock index rose 1.4 percent in active trade. Air Arabia, which could see increased business if transport links to Iran expand, rose 1.4 percent.
Arabtec gained 3.3 percent after confirming it had agreed terms with Egypt's Ministry of Housing for the first phase of a 280 billion Egyptian pound ($36.7 billion) plan to construct one million homes across the country.
Dubai property shares were generally active with DAMAC , the most heavily traded stock, surging 8.0 percent after the firm said it would consider taking an equity stake in a project to build a 50-storey mixed-use tower in central London - which would be its entry into Britain's market.
A handful of stocks in other Gulf markets rose because of hopes for Iran business. Oilfield services provider Gulf International Services (GIS) rose 2.6 percent, helping the Qatar index climb 0.6 percent.