* Dubai index posts best day in nearly three weeks
* Saudi's Tasnee drops on operational delay for titanium plant
* Banks drag on Abu Dhabi, Saudi Arabia
* Egypt's Iron and Steel rises on results
By Muvija M
Oct 30 (Reuters) - Dubai's blue-chip index rose sharply and marked its biggest intra-day gain in nearly three weeks, lifted by real estate and banks, while most major Gulf indexes dropped marginally on Tuesday.
The Dubai index added 1.1 percent, boosted by a near 3 percent gain in Emaar Properties and a 2.2 percent rise in Emirates NBD after it posted a double-digit jump in quarterly profit, led partly by higher net interest income.
Saudi Arabia's bourse was down 0.2 percent, hurt by a 0.5 percent dip in bellwether Al Rajhi Banking & Investment Corp and a 2.4 percent slide in Arab National Bank .
Petrochemical firm National Industrialization Company (Tasnee) fell 3.2 percent after it flagged operational delay for a titanium ilmenite smelter plant.
The index closed under its 200-day-moving average level, after briefly breaching it in the previous session.
But Herfy Food Services outperformed the index, rising 6.4 percent and marking its biggest intra-day gain since Jan. 2016 after an increase in its third-quarter profit.
On Monday, the top boss of Europe's biggest bank, HSBC, said that Saudi Arabia is unlikely to see a significant impact on its foreign trade and investment flows after the killing of Saudi journalist Jamal Khashoggi.
Norway's sovereign wealth fund last week also announced plans to more than double its investments in the kingdom after it is included in the fund's reference index.
Saudi's stock exchange data indicated on Sunday that foreign selling had slowed from the previous week, when it hit a record as the killing of Khashoggi spooked investors.
Abu Dhabi's index lost 0.3 percent, hurt by a 1.3 percent slide in First Abu Dhabi Bank and a 8.6 percent plunge in Gulf Pharmaceutical Industries.
The Egyptian blue-chip index gained 0.6 percent, with Eastern Co adding 3.2 percent and Citadel Capital rising 5.8 percent.
Investment firm Raya Holding soared nearly 10 percent after Egypt's regulator asked its Chairman Medhat Khalil and related group to make a buyout offer for the company.
Egyptian Iron And Steel Co gained 4 percent after reporting a smaller quarterly loss.
SAUDI ARABIA * The index was down 0.2 percent at 7,833 points. DUBAI * The index was up 1.1 percent at 2,744 points. ABU DHABI * The index was down 0.3 percent at 4,856 points. QATAR * The index was down 0.3 percent at 10,163 points. KUWAIT * The index was up 0.2 percent at 5,225 points. BAHRAIN * The index was down 0.2 percent at 1,313 points. OMAN * The index was down 0.2 percent at 4,421 points. EGYPT * The index was up 0.6 percent at 13,155 points. (Reporting by Muvija M in Bengaluru, editing by Ed Osmond)