A senior Iranian employee of the British Embassy in Tehran has been given a four-year prison sentence after being found guilty of fomenting violence at the behest of the British Government, The Times has learned.

Hossein Rassam, 44, the embassy’s political counselor, was sentenced in a closed courtroom this week, although the outcome is yet to be publicly announced. The Foreign and Commonwealth Office learned of his sentence on Tuesday and summoned the Iranian ambassador in protest. The British ambassador in Tehran has also lodged an official complaint.

Rassam was one of eight Iranian staff at the British Embassy arrested after mass street protests that erupted in cities across Iran following the disputed re-election of President Mahmoud Ahmadinejad on June 12.

Iran’s Supreme Leader, Ayatollah Ali Khamenei, blamed the protests by opposition supporters on a British plot to bring down the regime. Britain denies any involvement. The embassy staff was among hundreds of people rounded up and detained after the disturbances. Seven others were released without charge but Mr Rassam was sent to the notorious Evin prison in Tehran and charged with being the “kingpin” behind a British plot.

In a statement to The Times, David Miliband, the Foreign Secretary, said that Rassam’s sentence was unacceptable and urged that it be immediately repealed. He dismissed the charges against Rassam as “wholly without foundation.”

He added: “We understand the sentence can be appealed. I urge the authorities to conduct this quickly and overturn this harsh sentence. Such a decision is wholly unjustified and represents further harassment of embassy staff for going about their normal and legitimate duties.”

He was arrested on June 27 and accused of “acting against national security” — a catch-all charge for any kind of political dissent. He has worked at the embassy since 2004.

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