The 64-year-old from Tipperary was arrested while taking pictures of a mosque last October.
Bernard Phelan - the Irishman detained in Iran for more than six months - is to be released.
The Iranian Embassy in Dublin says he is to be pardoned and released on consular and humanitarian grounds.
The 64-year-old from Tipperary was arrested while taking pictures of a mosque last October.
The country accused him of anti-government propaganda, a charge he had denied.
He was initially sentenced to three and a half years, but it was increased to six and a half, with no explanation.

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