The minister, Mahmoud Alavi, told state TV on Monday that the "Zionist regime" was behind the plot. He didn't elaborate.
Denmark announced last week that a police operation there in September stemmed from an Iranian plot to kill an opposition activist. It said a suspect in the case, a Norwegian citizen of Iranian descent, has denied wrongdoing and is being held in pre-trial custody until Nov. 8.
The operation was linked to a separatist Iranian Arab group that Tehran has blamed for a September attack on a military parade in the city of Ahvaz that killed at least 25 people.