The National Council of Resistance of Iran (NCRI) said that a Revolutionary Guard garrison was on full alert from the night before the incident.

Hossein Abedini, of the organisation's foreign affairs committee, told a press conference in London that the move was a "meticulously concocted operation".

But the Revolutionary Guard plus Iran's foreign and intelligence ministries had decided that this fact should be covered up, he added.

"You can see that the clerical regime had in a premeditated attack arrested British soldiers in order to win concessions from the international community and divert attention from its nuclear projects," he said.

The NCRI said its information had come from within the Revolutionary Guards through the People's Mojahedin Organisation of Iran (PMOI), also known as the Mujaheddin e Khalq (MeK), a dissident movement banned in Britain, the European Union and the United States.

The organisation, which describes itself as the parliament in exile of the Iranian resistance, provided no substantive evidence to back up its claims.

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