Iranian President Hassan Rowhani said Washington's imposition of sanctions on Iranian Foreign Minister Mohammad Jawad Zarif was a "childish act" and stressed its inability to confront Iran.
He said in a speech that the United States claims that it wants dialogue with Iran, while imposing sanctions on the Minister of Foreign Affairs.
The Iranian president said that any party wants dialogue, its way through the Foreign Ministry and the head of this ministry.
The United States has imposed sanctions on Zarif for what it said had helped carry out a "reckless agenda" for Iranian leader Ali Khamenei, a US official said.
The United States on Wednesday imposed sanctions on Iran's foreign minister, including freezing its assets in the United States and punishing those it financially supports, the Treasury Department's foreign assets bureau said on its Web site.
Asked whether sanctions would affect the granting of a visa to visit the United Nations, Treasury Secretary Stephen Manuchen said the State Department would assess each case separately and that the law forbade the arrest of diplomats when traveling to the United Nations.
A US official confirmed that Washington would continue to exert extreme pressure on Iran while keeping room for diplomacy, adding that Trump's patience was running out.
The US 'reason for designating me is that I am Iran's "primary spokesperson around the world"
John Bolton, the US national security adviser, said in an interview with Fox News that the reasons for sanctions against Iran's foreign minister are that the United States sees in its activities the need to impose such sanctions.
But Zarif played down the importance and impact of US sanctions on him. "The reason for Washington's sanctions on me is that I am the main spokesman for Iran around the world," he said in a tweet on his Twitter account.
He added that the sanctions imposed by Washington "will not affect me or my family, because there are no property or interests outside of Iran."
In Republican reactions, Republican Senator Rand Paul said in a tweet on Twitter that if sanctions were imposed on a diplomatic figure, he would get less diplomacy, he said.
Democratic Senator Chris Murphy said in a Twitter comment on the decision that if his country's position was indeed willingness to negotiate with Iran, Washington might not have to impose sanctions on its chief negotiator. In reference to Zarif.