The U.S.-allied UAE, a federation of seven emirates and a major oil exporter that has supported Western counter-terrorism efforts in the region, has been spared any attack by al Qaeda and other insurgency groups.

But some of its emirates have seen a rise in Islamist sentiment in recent years, and Dubai, a business and tourism hub and cosmopolitan city that attracts many Westerners, could make an attractive target for Islamist militants, analysts say.

Those arrested had acquired materials and equipment for use in what WAM called terrorist operations.

"The security authorities in the UAE, in coordination with the related security parties in Saudi Arabia, announced the arrest of an organised cell from the deviant group that was planning to carry out actions against national security of both countries and some brotherly states," WAM said without elaborating.

The phrase "the deviant group" is often used by authorities in Saudi Arabia to describe al Qaeda members.

Emirati political analyst Abdulkhaleq Abdullah told Reuters he believed it was the first time the UAE had announced a suspected attack plot of regional significance.

It "looks like it is a big one, mainly because it includes Emirati citizens and is not confined to the UAE but also has a regional dimension."

In August, Saudi authorities arrested a group of suspected al Qaeda-linked militants - mostly Yemeni nationals - in Riyadh.

Saudi Arabia has arrested thousands of suspected militants since the 2003-2006 attacks on residential compounds for foreign workers and on Saudi government facilities in which were dozens of people were killed.

The United States has poured aid into Yemen to stem the threat of attacks from al Qaeda in the Arabian Peninsula AQAP.L and to try to prevent any spillover of violence into Saudi Arabia, the world's top oil exporter.

In 2010, AQAP, a merger of al Qaeda's Yemeni and Saudi branches, said it was behind a plot to send two parcel bombs to the United States. The bombs were intercepted in Britain and Dubai.

The UAE has escaped the upheaval that has shaken the Arab world but moved swiftly to stem any sign of political dissent by detaining more than 60 local Islamists this year over alleged threats to state security and links to a foreign group.

Those detainees, who belong to an Islamist group called al-Islah, have confessed to setting up a secret organisation with an armed force whose aim was to take power and establish an Islamic state, local media reported in September. Islah denied the accusations.

Many of the detained Islamists come from the more religiously conservative northern emirates such as Sharjah and Ras al-Khaimah, which produced one of the September 11 hijackers.

In May 2002, al Qaeda militants sent a letter to UAE authorities saying continued UAE cooperation with Washington in arresting what it called holy warriors would "bring the country into an arena of conflict," according to al Qaeda documents captured by the U.S. military and published by the Combating Terrorism Center at the U.S. military academy at West point. (Reporting by Rania El Gamal and William Maclean; Editing by Jon Hemming)

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