* Qatar index comes within 5 percent of pre-embargo level
* Mesaieed Petrochemical and GISS surge
* But Ezdan hit by annual profit drop, dividend halt
* Saudi's SABIC rises on Swiss acquisition news
* Dubai's Amanat climbs after raising Taaleem stake
DUBAI, Jan 25 (Reuters) - Stock markets in the Gulf gained on Thursday, supported by the rise in Brent oil to a three-year high above $70 a barrel, as Qatar continued a strong rally and the top Saudi Arabian petrochemical producer climbed after acquisition news.
Qatar's main index rose 1.1 percent, gaining for a fourth straight day. Corporate earnings have suggested that damage to the economy from an embargo imposed by other Arab states has been less serious than feared, and the index is now within 5 percent of its pre-embargo level last June.
Mesaieed Petrochemical surged 5.5 percent and drilling rig provider Gulf International Services gained 3.2 percent in active trade. Both firms' revenues could benefit from higher oil prices.
But property firm Ezdan Holding tumbled 6.8 percent after reporting a drop in annual net profit to 1.69 billion riyals ($464 million) from 1.81 billion, and deciding not to pay a 2017 dividend. In the first nine months of the year, profit had risen 9 percent.
The Saudi index was 0.6 percent higher, with Saudi Basic Industries Corp adding 2.0 percent to hit its highest level since early 2015.
It agreed to acquire a 24.99 percent stake in Swiss specialty chemicals maker Clariant AG, becoming the Swiss company's largest shareholder. SABIC did not say how much it was paying, but the 24.99 percent stake was worth $2.4 billion based on market capitalisation.
However, Saudi Fertilizers fell 2.5 percent after reporting fourth-quarter net profit dropped to 62.5 million riyals ($16.7 million) from 268.4 million riyals a year ago, mainly because of a scheduled shutdown of facilities but partly because of a rise in fixed and variable costs. In the first nine months, net profit rose 6 percent.
Dubai's index edged up 0.2 percent with most stocks trading narrowly, although real estate firm Deyaar, the most heavily traded stock, climbed 1.6 percent.
Education and healthcare investor Amanat added 3.5 percent after saying it had bought an additional 40 million shares in schools operator Taaleem Holdings for 52 million dirhams ($14.2 million), making it the biggest shareholder with 21.7 percent.
Egypt's market was closed for a public holiday.
* Index gained 0.6 percent to 7,522 points.
* Index rose 0.2 percent to 3,469 points.
* Index gained 0.4 percent to 4,644 points.
* Index climbed 1.1 percent to 9,460 points.
* Index rose 0.2 percent to 6,652 points.
* Index gained 0.4 percent to 1,342 points.
* Index rose 0.7 percent to 5,008 points. (Editing by Kevin Liffey)