Mr Boroujerdi, Chairman of the Iranian Parliament's National Security and Foreign Policy Commission, said that although foreign diplomats have diplomatic immunity, "they have to observe the country's regulations".

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This grants immunity for actions a foreign government takes when it is acting as a government, but not for actions taken when it is acting as, for example, a commercial enterprise, which might occur when the government in question owns a company doing business in the United States.

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It followed the lifting of an immunity deal in 2009 preventing foreign nationals being charged with criminal offences.

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