Iran is "unquestionably in default of the spirit of the JCPOA", or Joint Comprehensive Plan of Action, that went into effect in January 2016 after years of negotiations, the official said.
"We receive contradictory signals, so we don't know how to interpret it", Zarif told the Council on Foreign Relations in NY, adding that "Iran is serious about the nuclear deal" and will continue to comply with its restrictions on nuclear activities in exchange for the lifting of nuclear-related sanctions.
But with the introduction of a Senate bill that would impose new sanctions on Iran aimed at its ballistic missile program, the language of which the nonpartisan Arms Control Association calls "overly broad and imprecise", critics say the USA has not met the deal's terms, endangering the agreement.
Trump administration officials, briefing reporters on Monday on the decision, said new economic sanctions against Iran were being prepared over its ballistic missile programme and for contributing to regional tensions.
"Iran is a serious partner for all these countries in fighting a common enemy because we believe at the end of the day. these extremist forces are as much a threat against us, but even more a threat against them", Zarif said.
A senior administration official said Iran was judged in compliance of the 2015 nuclear deal but that Trump and Secretary of State Rex Tillerson believed Iran "remains one of the most risky threats to USA interests and to regional stability".
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Paul, who has criticized the bill for not being conservative enough, has also said he will vote against the bill. I think it would be extremely close.
The deal, though, rests not just on the USA and those European allies - France, the United Kingdom and Germany - but also on China and Russian Federation.
Trump's "commitments to fixing these flaws remains steadfast", an official said when asked why the administration is certifying Iran's compliance despite Trump calling it the worst deal he's ever seen.
Iranian Foreign Minister Mohammad Javad Zarif said on Monday that he hopes Yemen's war will not spark direct confrontation between Iran and Saudi Arabia and that they can work together to end the conflict in the country and Syria.
"The secretary of State is in the process as we speak of certifying to the Congress that the conditions that are laid out in the [Iran Nuclear Agreement Review Act] have been met based on information available to the United States", the official said.
Tehran Iran has blamed the United States of not fulfilling its obligations under the nuclear deal, dubbed as an historical document undersigned in Vienna in 2015 between Iran and five permanent members of the United Nations Security Council and Germany. Iran, in exchange for adhering to the agreement negotiated in 2015 between itself, the United States, and global powers, gets sanctions relief.
While he has never spoken with Tillerson, Zarif said lower-level talks on the implementation of the Iran deal continue.