Rouhani's remarks came after Iran's ambassador to the United Nations said the US would have to redraft its proposed resolution on the issue after being "rebuffed" by Security Council members.

The ban on selling weapons to Iran is set to be progressively eased from October under the terms of Resolution 2231, which blessed the Iran nuclear deal that world powers agreed in July 2015.

But a UN embargo on materials and technology that Iran could use for its ballistic missile programme is to remain in place until 2023.

The European Union has said it will continue to enforce its own embargo against Iran after the lifting of the first UN embargo.

Under the accord officially known as the Joint Comprehensive Plan of Action, Iran committed to limiting its nuclear programme in exchange for sanctions relief.

The JCPOA has been on life-support since the US withdrew from it and reimposed unilateral sanctions in 2018.

Iran has since taken small but escalatory steps away from compliance with the agreement as it presses for the sanctions relief it was promised.

"We have great hopes that America will fail," Rouhani told a televised meeting of his cabinet on Wednesday.

"We have great hopes that America will realise its failure and see its isolation," the Iranian president said.

- 'Blatant violation' -

"But our stance in any case is clear. If such a resolution comes to pass... it means a blatant violation of the JCPOA," he added, warning the "consequences will rest with the perpetrators of this act".

Iran's envoy to the UN, Majid Takht Ravanchi, said on Wednesday that the US "was forced to retreat" from its draft resolution after being "rebuffed by UNSC members" and had to propose a fresh version.

"The new draft is similar -- in its NATURE and GOAL -- to the previous. Confident that the Council will -- again -- reject this move," he tweeted.

Foreign Minister Mohammad Javad Zarif also accused the US of "using a Security Council mechanism to destroy" the UN.

Zarif said the new draft was a "five-page resolution reduced to five sentences", and added that by presenting it as new, the US was disrespecting Security Council members.

The UN and US have yet to confirm this, however.

The original US text, seen by AFP, effectively called for an indefinite extension of the embargo on Iran and used hawkish rhetoric.

European allies of the United States -- Britain, Germany and France, who along with Russia and China, are parties to the JCPOA -- have voiced support for extending the conventional arms embargo but their priority is to preserve the nuclear deal.

Washington has threatened to use a contested argument that it remains a "participant" in the JCPOA -- despite its withdrawal -- and if UN sanctions are not extended, it can force their return if it sees Iran as being in violation of the accord's terms.