“America should forget forever the idea of one-sided negotiations under the shadow of a threat,” Qassemi was quoted by the semi-official Tasnim news agency as saying on Wednesday.
His remarks come in reaction to US President Donald Trump’s statement, who on Tuesday said he was ready “to make a real deal” with Iran.
According to state-run IRNA news agency, Qassemi also said that Iran has filed an official letter of objection to the Swiss embassy in Tehran, which oversees US diplomatic relations in Iran, in response to US Secretary of State Mike Pompeo’s remarks.
“The level of corruption and wealth among Iranian leaders shows that Iran is run by something that resembles the mafia more than a government,” Pompeo said in a speech on Sunday amid rising tensions between the two countries.
Earlier this week, Trump and his Iranian counterpart Hassan Rouhani traded angry threats. Rouhani warned Trump not to escalate tensions with Iran, saying a confrontation with the Islamic Republic would be the “mother of all wars”.
“Do not play with the lion’s tail or else you will regret it,” Rouhani said in a televised speech in Iran’s capital Tehran.
Trump hit back on Monday in a tweet directed specifically at Rouhani.
To Iranian President Rouhani: NEVER, EVER THREATEN THE UNITED STATES AGAIN OR YOU WILL SUFFER CONSEQUENCES THE LIKES OF WHICH FEW THROUGHOUT HISTORY HAVE EVER SUFFERED BEFORE. WE ARE NO LONGER A COUNTRY THAT WILL STAND FOR YOUR DEMENTED WORDS OF VIOLENCE & DEATH. BE CAUTIOUS!
— Donald J. Trump (@realDonaldTrump) July 23, 2018
The two nations have been at loggerheads since Trump pulled out from a 2015 nuclear deal signed with world powers.
Under the landmark deal signed in Vienna, six world powers – the US, UK, France, Germany, Russia, China and the European Union – offered Iran more than $110bn a year in sanctions relief and a return to the global economy in exchange for halting its drive for nuclear weapons.
Since its withdrawal from the deal in May, Washington has threatened to reimpose sanctions and attempted to prevent countries from purchasing Iranian oil. In response, Tehran hinted it may block regional oil exports if its own sales are halted.
At least 18.5m barrels of oil has moved via the strategic passageway – Strait of Hormuz – every day in 2016, according to a US energy department report.
The strait, located between Iran and Oman, is also used by Gulf countries who rely on safe passage through the narrow chokepoint to export their oil and gas.
Trump has previously suggested that Iranian leaders are going to request a new deal, but Iran has rejected talks on several occasions.
Iran said it was interested in keeping the nuclear deal alive, but only if the remaining powers can guarantee that it will not face economic isolation under Washington’s sanctions.
Europe opposes the US’ decision to leave the agreement and has vowed to find ways of maintaining its trade ties with Iran.