The diplomat said the crackdown meant he could not stay in his role
An Iranian diplomat in Oslo has resigned in protest at his government's crackdown on opposition supporters, Norwegian media have reported.
Norway's NRK TV quotes Iranian consul Mohammed Reza Heydari as saying the treatment of protesters last month made him realise he "couldn't continue".
Opposition websites in Iran say he has defected and is seeking asylum.
But Iran dismissed the report as baseless, saying the diplomat's tenure had ended and he would return to Iran.
"A diplomat returns to the country when his mission is finished in another country," Foreign Ministry spokesman Ramin Mehmanparast told Reuters.
He said diplomats sometimes stayed on longer in a country for person reasons.
At least eight people died in clashes with police during anti-government protests in Tehran at the end of December.
The Norwegian Foreign Ministry told Reuters news agency it was aware of the reported resignation but not been officially contacted.
The protest began after President Mahmoud Ahmadinejad's controversial re-election in June and have grown into the biggest challenge to the government since the 1979 Islamic revolution.