The United States re-imposed tough, unilateral sanctions against Iran on Tuesday, bringing back into effect tough penalties that had been lifted under a historic, multi-party nuclear agreement that President Donald Trump abandoned in May.
Heavier U.S. sanctions, aimed at Iran's oil sector, are due in November.
They have been delighted by the scattered protests that have already emerged as the Iranian economy crumbles, and will risk more in the hope of greater gains. USA imports of food and carpets from Iran are also restricted.
They aim "both to coerce Tehran to change its behaviour, as well as to maintain the deterrent power of secondary sanctions" in targeting non-US companies doing business with Tehran, Mr Taleblu told The National.
US Secretary of State Mike Pompeo said sanctions are an important pillar in US policy toward Iran and will remain in place until the Iranian government radically changes course.
"Preserving the nuclear deal with Iran is a matter of respecting global agreements and a matter of worldwide security", she said, in a joint statement on Monday along with the foreign ministers of France, Germany, and the United Kingdom.
Trump's contempt for the nuclear deal dates back to his time as presidential candidate and on May 8, he made good on a pledge to pull America out of the worldwide agreement.
She made the announcement on the same day renewed US trade sanctions against the Islamic Republic restarted.
Asked about any possible exemptions to the renewed sanctions, officials said they would examine any requests on a case-by-case basis. "Negotiations with sanctions doesn´t make sense".
With US sanctions set to return against Iran on Tuesday, Zarif acknowledged there were hard times ahead.More news: In one tweet, Trump confuses everything about California bushfires
Trump said the new sanctions target the Islamic Republic's automotive sector, its trade in gold and other precious metals, along with its currency, the Iranian rial, and other financial transactions.
Mr. Erdan was speaking after European Union foreign policy chief Federica Mogherini said the bloc is actively encouraging enterprises to increase their business with Iran.
In a joint statement on Monday from Britain, France, Germany and the European Union as a bloc, they said: "We deeply regret the reimposition of sanctions by the U.S".
John Glaser, director of foreign policy studies at the Cato Institute, noted that the U.S. sees the sanctions "as a tool to pressure Iran to come back to the negotiating table to rehash the nuclear deal on terms more to Trump's liking".
Many large European firms are leaving Iran for fear of United States penalties, and Mr Trump warned of "severe consequences" against firms and individuals that continued to do business with Iran.
European officials have condemned the renewed sanctions as illegal and in violation of a UN Security Council resolution, vowing to counter the U.S. measures and save the Iran nuclear accord. "That is not going to happen", said John Glaser of the Cato Institute.
US trade with Iran stood at $258 million (Dh948m) in 2016, according to the US Census Bureau, while exports to Iran from the European Union, which will be affected by secondary sanctions, were worth $13 billion a year ago.
There have been rumours that Trump and Rouhani could meet in NY in September on the sidelines of the UN General Assembly - though Rouhani reportedly rejected USA overtures for a meeting at last year's event.
Severe reporting restrictions have made it impossible to verify the swirl of claims coming through social media.