DUBAI (Reuters) - Gulf Arab states, hosts to U.S. and Western military bases, fear the discovery of a purported Iranian spy ring in Kuwait will make it harder to stay out of the fray of any conflict over Iran's nuclear program.
The ensuing tensions following the Kuwaiti arrests, details of which remain scant, may further polarize Gulf states against non-Arab rival Tehran as a global row over Iran's nuclear ambitions heats up.
News of the round-up, if proven, could also prompt security clampdowns by Gulf states aimed at ferreting out any more potential spies governments fear may be scouring their land for retaliatory targets in the event of a U.S. strike on Iran.
"What they are searching for is not being caught in the crossfire of a potential military strike on Iran," said Theodore Karasik of the Institute for Near East and Gulf Military Analysis.
"When you have the presence of spy rings and this drifting more toward the western position, it makes the situation a little more dangerous," he said.
Tehran denies running spies in Kuwait, whose ties with the Islamic Republic have improved after turning poisonous during the 1980-88 Iran-Iraq war over Kuwait's backing of Iraq.
The West suspects Iran, just across the water from the Western-allied Gulf states, is seeking nuclear weapons capability. The United Nations imposed this week new sanctions against Iran, which says it wants only to generate electricity.
But if diplomacy fails, neither the United States nor Israel, the only assumed nuclear power in the Middle East, have ruled out military action. That spells danger for oil-exporting Gulf states, as Iran has threatened to hit back at Israel and U.S. bases in the Gulf if attacked.
The United States has already grown its land- and sea-based missile defense systems in several Gulf countries to counter what it sees as Iran's growing missile threat.
"These (Gulf Arab) countries now are assuming that definitely the (Iranian) revolutionary guard is already there in their country," Mustafa Alani of the Gulf Research Center said.
"If it (the Kuwait accusation) is proven ... I think we are going to witness a major close look by intelligence in each country," he added.
The United States has myriad air and naval installations in Gulf Arab states, some of which are little more than 200 km (124 miles) from Iran's coast. The U.S. Central Command keeps its forward headquarters in Qatar, and Bahrain hosts the U.S. Navy's
Kuwait hosts Camp Arifjan, a vast U.S. logistics base in the desert south of the capital that serves as a staging ground for U.S. forces deploying in Iraq.
Kuwaiti media said in May authorities had detained a number of people -- Kuwaitis and foreigners -- suspected of spying for Iran, and the independent al-Qabas daily said they were accused of gathering information on military sites in Kuwait.
Kuwait, which has banned media coverage of the case, has said only that it was holding several people in an unspecified security probe and that details published in the media were inaccurate. It has not clarified the matter.
That the arrests happened in Kuwait, whose ties with Iran were among the better in the region, could spread alarm for other Gulf states whose own relations with Iran are more tense.
Saudi Arabia, home to Islam's holiest site, sees Tehran as a rival for regional sway, and a dispute between Iran and the United Arab Emirates over three Gulf islands picked up steam in recent months, despite strong trade ties between the states.
Bahrain had a brief spat last year with Tehran after an adviser to Supreme Leader Ayatollah Ali Khamenei was quoted as saying Iran had sovereignty over the tiny kingdom, where a Sunni family rules over a Shi'ite majority.
"The fear is that (if it were) equipped with a nuclear bomb, Iran will be able to fulfill its self-perception as the region's powerhouse to be able to bully the GCC (Gulf Cooperation Council) states at its will," IHS Global Insight Middle East analyst Gala Riani said.
"In the case of an Israeli attack on Iran, the GCC states would likely fall back on their well-versed quietist approach, with their priority being to avoid inflaming the situation," Riani said. "Privately some of them might welcome an attack that could retard the Iranian nuclear program."
Sunni-led Gulf countries, with often significant and marginalized Shi'ite minorities, also worry about Iran's sway on their own Shi'ite populations. If the existence of an Iranian spy ring in Kuwait is proven, Gulf states could respond harshly.
A diplomat familiar with the investigation said the ring was made up of eight people -- all Shi'ites -- including Kuwaitis, Lebanese and Bahrainis.
Kuwait has in the past arrested Shi'ites for alleged plots in the 1980s to destabilize the country, including an attempt to kill Kuwait's ruler and the hijacking of a Kuwaiti plane to demand the release of Shi'ite prisoners.
Kuwait deported some 27,000 expatriates, mostly Iranians, in 1985 and 1986 and stepped up security after Tehran fired missiles at its oil installations and attacked Kuwaiti tankers.
Analysts said Gulf states could slap entry or residency restrictions on Iranian expatriates, several hundred thousand of whom live in Gulf states. Some could be selectively deported.
But Iran, whose foreign ministry has said the reports were an attempt by enemies such as Israel to sow regional division, was likely to feel it had to watch its back.
"They have to collect information on the American bases or the capabilities of the GCC states because they can see on the horizon there is something going to happen sooner or later," said Alani of the Gulf Research Center.
But a senior Arab diplomat in Riyadh said reports about the spy cell's size and importance may have been exaggerated, and cited a "general paranoia" over Iran's role in the region.
"But if this affair gets confirmed, it will also prompt predominantly Sunni Arab countries to put their Shi'ite community under greater scrutiny," he said.