Smash hit

The incident surprised many Iran experts who said both Washington and Tehran had made recent efforts to “de-escalate” their confrontation. One sceptical analyst said: “Have you ever heard of a suicide bomber saying, 'hey, I’m going to blow myself up right now'?"

Washington will want to determine whether the Iranian action was the result of overzealous Revolutionary Guards in the area acting on their own initiative or whether an intended provocation was planned in Tehran.

The second scenario would suggest Tehran was underlining its vocal opposition to Mr Bush’s Mid-East visit. His rare trip to the region is aimed at bolstering Arab support against Iran’s nuclear programme as well as shoring up troubled peace moves between the Israelis and Palestinians.

The narrow Strait of Hormuz at the mouth of the Persian Gulf is one of the world’s most sensitive strategic locations, with at least a fifth of the world’s crude oil supply passing through it.

Iranian military commanders have repeatedly warned that if their country is attacked by the US, blocking the Strait’s narrow choke-point to the Persian Gulf would be one of several means of retaliation. Oil prices rose some 30 cents to over $98 a barrel after news of the incident before slipping back.

Iranian analysts urged caution, saying there had been public attempts by Tehran and Washington recently to ease tensions. The US military had also mis-read Iranian radio communications in the past, most notably in 1988 when the USS Vincennes, an American guided missile cruiser, mistakenly shot down an Iranian civilian airliner over the Strait of Hormuz, killing all 290 passengers and crew.

“I’d take this with a very large grain of salt until we get more details… who knows, this could be a turning point or it could be an isolated incident with no significance at all,” Professor Gary Sick, an Iran specialist at University of Columbia, said. “This is contrary to all the positive signals we’ve seen in recent weeks from both sides. This strikes me really as an aberration,” Prof Sick, who served on the US National Security Council under Presidents Ford, Carter, and Reagan, told The Times.

US military commanders in Iraq have recently said the reduction of violence in Iraq was in part due to Iran stemming the flow of weapons to Iraqi militias and gave Tehran some credit for the observance of a ceasefire by Moqtada al-Sadr’s Shia Mehdi Army in Iraq.

Last week, Ayatollah Ali Khamenei, Iran’s Supreme Leader, stated that relations with the US could be restored in the future. While he insisted now was not the time to mend fences, some analysts speculated he was sending a message to US presidential candidates that less hostile American policies could lead to reconciliation.

“Both sides have made an effort to de-escalate the conflict,” Karim Sadjadpour, an Iran expert at the Carnegie Endowment for International Peace in Washington said. “But there are forces in both the US and Iran who don’t want to see an improvement of ties… and whenever efforts are made to reduce the tension they often-times create incidents to sabotage this confidence-building,” he told The Times.

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