DUBAI, July 12 (Reuters) - Egypt's stock market dipped for a second day in early trading as investors took profits from a rally inspired by future currency devaluation speculation, while Saudi Arabia's bourse rose for the third straight session.

The main measure in Egypt .EGX30 fell 1.5 percent in early trade, having ended Monday 0.2 percent lower.

The index had surged 7.7 percent in the two prior sessions straddling the Eid al-Fitr holiday, following comments from the central bank governor that the Egyptian pound should be a market-based currency where demand and supply set the price.

Most stocks traded down. Global Telecom Holding GTHE.CA slipped 2.4 percent, having avoided the widespread falls of the previous day to close at a fresh 15-month high.

Saudi's index .TASI rose for a third day since it resumed trading after the Eid holiday, up 0.6 percent. Among the largest gainers at the top end of the market were Ma'aden 1211.SE and PetroRabigh 2380.SE , which advanced 2.7 percent and 2.9 percent respectively.

Qatar's bourse .QSI dipped 0.6 percent from the previous day's 11-week high, with Qatar National Bank QNBK.QA down 0.7 percent ahead of the publication of its second-quarter earnings.

The largest lender in the Middle East and Africa is due to report its results at around 1000 GMT, with analysts' average expectation for a 10 percent year-on-year increase in net profit. urn:newsml:reuters.com:*:nL8N19W07R

Oman's index .MSI rose 0.3 percent in muted trading.

Oman Cement OCCO.OM traded flat despite reporting an 83.9 percent jump in second-quarter net profit after tax, according to Thomson Reuters calculations.

In the United Arab Emirates, Dubai's measure .DFMGI was on course for a sixth straight positive session either side of Eid, gaining 0.8 percent. However, Abu Dhabi's exchange .ADI traded down for the third straight day at 0.2 percent lower.

(Reporting by David French; Editing by Andrew Heavens) ((davidj.french@thomsonreuters.com; +971 4 362 5864; Reuters Messaging: davidj.french.thomsonreuters.com@reuters.net))