Iran has trained secret networks of agents across the Gulf states to attack Western interests and incite civil unrest in the event of a military strike against its nuclear programme, a former Iranian diplomat has told The Sunday Telegraph.

	Western interests in Dubai could be attacked the Iranian regime's agents

Spies working as teachers, doctors and nurses at Iranian-owned schools and hospitals have formed sleeper cells ready to be "unleashed" at the first sign of any serious threat to Teheran, it is claimed.

Trained by Iranian intelligence services, they are also said to be recruiting fellow Shias in the region, whose communities have traditionally been marginalised by the Gulf's ruling Sunni Arab clans.

Were America or Israel to attack Iran, such cells would be instructed to foment long-dormant sectarian grievances and attack the ex-tensive American and European business interests in wealthy states such as Dubai and Saudi Arabia. Such a scenario would bring chaos to the Gulf, one of the few areas of the Middle East that remains prosperous and has largely pro-Western governments.

The claims have been made by Adel Assadinia, a former career diplomat who was Iran's consul-general in Dubai and an adviser to the Iranian foreign ministry. They came as Mahmoud Ahmadinejad, the Iranian president, made a formal visit to Saudi Arabia yesterday in what was widely seen as an attempt to defuse growing Sunni-Shia tensions in the Middle East.

Saudi Arabia has accused Iran of backing Shia death squads killing Sunnis in Iraq, and of backing the Lebanon-based Hezbollah militia in its efforts to bring down the government in Beirut. Meanwhile, a US naval build-up has continued in the Gulf waters south of Iran, a move intended to show Washington's readiness to strike against Teheran's nuclear installations for defying UN orders to cease uranium enrichment.

Mr Assadinia, who fled Iran after whistle-blowing on corruption among the country's all-powerful theocrats, said: "The Iranian government believes that to survive it needs permanent bases throughout the Middle East. Anybody who contemplates threatening or invading Iran will have those cells unleashed against them."

Mr Assadinia, 50, served for two years at the Iranian consulate in Dubai, which he says was also used as a conduit for illicit funding of Hezbollah, the Lebanon-based Shia militant group that waged a six-week war with Israel last summer.

Iranian foreign ministry agents would regularly pass through with suitcases containing up to £11 million, using diplomatic baggage channels to bypass customs scrutiny.

"The amounts varied, but it would come through on average twice a month," he said. "I would see it sometimes. As far as I know, that money always went to Hezbollah."

His consulate, he said, was a hub for regional intelligence operations because of the huge number of Iranians working in Dubai, which is the main trade port for the Middle East. Its skyscrapers and industrial estates are home to 4,000 Iranian businesses, providing easy cover for espionage.

Other intelligence activities included running nightclubs and prostitution rings, where carousing officials and diplomats could be lured into "honey trap" blackmail operations, and organising Iranian expatriates - there are an estimated 500,000 in the Gulf - to act as double agents.

"People were encouraged to tell the Europeans that Iran wanted a good relationship with them, when in fact Iran was involved in terrorism," said Mr Assadinia. Asked whether it was an attempt to divert attention from a covert nuclear weapons programme, he replied: "Precisely".

Of greatest potential concern is his claim that Iran has established networks of agents to liaise with Shias across the Gulf, particularly in Bahrain, Abu Dhabi, Sharjah and Saudi Arabia.

Politically disfranchised Shia communities exist throughout the region. Teheran has backed their claims for more power ever since the Iranian Islamic revolution in 1979, but could now also mobilise them as a way of deterring the Gulf's Sunni rulers from supporting American efforts to stop Iran's nuclear programme. Although most of the Gulf states oppose US intervention against Iran, privately they fear that a nuclear-armed Teheran would dominate the Middle East.

Allegations of Iranian agents operating in the Gulf have surfaced before, but it is rare for them to be spelt out in detail by a former regime official. Mr Assadinia named a hospital in Dubai - which The Sunday Telegraph has not identified for legal reasons - as one place where many doctors and nurses also worked for Iranian intelligence.

He left his post in Dubai in 2002 and was granted asylum in Europe a year later, having undergone "intimidating" interrogations by Iranian intelligence agents in Teheran. Mr Assadinia plans to give more detail of his claims at a meeting later this month at Westminster, organised by the British Awhazi Friendship Society, which lobbies Parliament, the European Union and the United Nations. He hopes his disclosures will encourage other Iranian officials to follow suit.

"The government sees itself as strong, but in fact it is like Saddam Hussein before he was overthrown - very fragile and brittle within," he added.

A spokesman for the Iranian embassy in London described Mr Assadinia's claims as "baseless and fabricated". He said the Iranian diplomatic presence in the Gulf was entirely legitimate and described the friendship society as an "illegal" organisation dedicated to stirring up trouble between Iran and its neighbours.