Gunmen dressed in Iraqi Army uniforms snatched an Iranian diplomat off the streets of Baghdad, elevating still further tensions with Washington as Tehran said that it held the US responsible for his safety.

The Iranian Government said that Jalal Sharafi, the second secretary at its embassy in Baghdad, was seized on Sunday by an Iraqi commando unit which operated directly “under the supervision of the American forces in Iraq.” Mr Sharafi was driving to open a new Iranian bank.

US officials denied that coalition troops had any involvement in the operation, but Muhammad Ali Hosseini, Iran’s Foreign Ministry spokesman, said bluntly: “Iran holds American forces in Iraq responsible for the safety and life of the Iranian diplomat.”

The kidnap follows a series of flashpoints between Iran and the US - which has accused Tehran of supplying insurgents with sophisticated weapons to attack coalition forces and recently authorised US troops to kill or capture Iranian agents deemed to be a threat.

US forces raided an Iranian Government office in Erbil and arrested five employees last month. There have also been leaks suggesting Iranian involvement in a well-planned abduction and execution of five US soldiers in Karbala. Gunmen in coalition uniforms and vehicles passed through security cordons and snatched the soldiers during a meeting with Iraqi officials.

Hassan Kazemi Qomi, the Iranian Ambassador to Baghdad, said that the gunmen used American vehicles and the diplomat’s seizure appeared to be “within the framework of the US President’s order to step up encounters with Iranians.”

There is widespread conviction in Iraq that insurgents and militias have infiltrated the Ministry of Defence and Interior Ministry security forces.

Lou Fintor, a US Embassy spokesman, said: “There appear to be conflicting accounts of this alleged incident and we are in the process of trying to determine the facts.”

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