"We will not give up our righteous stance," Qassemi said at a news conference.
The Fars News Agency said Qassemi took the position that an oil embargo against Iran was "completely impractical … since it will leave severe impacts on the world oil market."
The European Union has said it would join the embargo led by the United States. The EU has said it would wait until midsummer to join, which would give time for other producers to make up the difference in oil supplies that will be lost when it drops Iran as a supplier.
Iran, in turn, is working on a law that would, in retaliation, ban exports to Europe.
Iran's government-supported Islamic Republic News Agency said Qassemi reiterated that pledge.
"Iran will cut oil export to certain countries and supply of oil will continue to other European countries which have contracts on purchase of oil from Iran," he said.