The so-called Iran Freedom Policy and Sanctions Act was introduced by Republican representative Peter Roskam and backed by his fellow GOP member Liz Cheney, the daughter of scandal-hit former US Vice President Dick Cheney, on Thursday.
The proposed legislation makes clear what any effective agreement would have to contain, Cheney said in a statement.
The United States, under President Donald Trump, has been aggressively pushing against the agreement.
However, the deals other signatories -- the UK, France, Russia, China, and Germany -- have hailed it as a diplomatic triumph and a pillar of regional and international diplomacy.
They have also praised Irans full compliance with its side of the agreement, called the Joint Comprehensive Plan of Action (JCPOA), warning Washington against attempts to link unrelated issues to the accord, which has been endorsed by a UN Security Council resolution.
PressTV-EU powers reaffirm support for Iran nuclear deal
European powers have reaffirmed their determination to preserve Irans nuclear agreement against the backdrop of US efforts to undermine the landmark multinational deal.
Trump has, on occasions, threatened to tear up the agreement or withdraw USs participation in it despite the fact that the deal is multinational.
A robust defense of the agreement came earlier at a United Nations Security Council meeting.
Russias Foreign Minister Sergei Lavrov said at the meeting that possible collapse of the deal would send an alarming message to the world, while UN chief Antonio Guterres noted that it was in the worlds interest that the agreement be preserved.
PressTV-Iran nuclear deal failure would be alarming, Russia warns
Lavrov says abandoning the Iran nuclear deal would cause it to fail and this would send an "alarming" message to other countries.
Cheney further said a deal with Iran would need to at a minimum, authorize anywhere, anytime inspections including inspections of military facilities; disclosure of all past and present, military and civilian nuclear activity; a ban on weapons-grade enrichment; and a restriction on ballistic missile development.
Iran asserts that its nuclear activities have never had any military dimension -- something repeatedly verified by the International Atomic Energy Agency (IAEA), which is tasked with monitoring the technical aspect of the JCPOAs implementation.
Tehran had also the so-called possible military dimensions (PMD) of its nuclear program case closed in December 2015, when the IAEA said it had found no indications of diversion of nuclear material for non-civilian objectives in Tehrans nuclear work.
Since Trumps inauguration last year, the US has also imposed many rounds of sanctions against legal and natural persons, associating them with Irans conventional missile program. Tehran has slammed those bans a violation of both the letter and spirit of the deal.
Cheney added that the legislation will ensure that sanctions on Iran will only be relaxed if Iran meets these crucial requirements, said Cheney, criticizing the current agreement for allegedly delivering "sanctions relief and cash payments to Iran in exchange for unverifiable promises.
The agreement has lifted all nuclear-related sanctions against Iran. Since its conclusion, however, the US has been cautioning foreign enterprises against re-entering transactions with Iran.
A parallel bill aimed at toughening the nuclear deal is under consideration in the Senate.
Irans Foreign Ministry has said it will not accept any amendments in this agreement.
Deputy Foreign Minister Abbas Araqchi reaffirmed on Tuesday that the JCPOA drew a line between the missile program and the nuclear issue, saying that no party could now claim that Irans missile tests violate the nuclear agreement. He emphasized that the countrys defense program is not up for either negotiation or compromise.
