He added that the Joint Comprehensive Plan of Action, the formal name for the nuclear deal, is not just a deal between Iran and the USA and Iran has interaction with the other five signatories. "Whatever tactical disagreements may exist between the US and Europe, there remains a rough strategic consensus about Iran among the allies".
The waivers were first issued by the Obama administration and are America's part of the deal's central bargain.
But supporters hailed Thursday's move, in which the US Treasury announced new sanctions on non-nuclear issues even as Trump's administration grudgingly maintained sanctions relief.
USA diplomats have approached European officials to see if they would join in demanding an extension to limits on Iran's uranium enrichment that are set to expire in 2025 and 2030 under the nuclear accord reached in 2015, according to people familiar with the discussions.
Director for nonproliferation policy at the Arms Control Association Kelsey Davenport expressed concern that Washington's possible plans to scrap the Iran deal, called the Joint Comprehensive Plan of Action, will eliminate any possibility of resolving inducing North Korea's nuclear weapons crisis through negotiation. U.S. media reports said Trump agreed to those certifications only "reluctantly".
If the president decides by the October 14 deadline to decertify the Iran deal, it would kick off a 60-day period in which Congress must decide whether to reinstate sanctions on Iran by a simple majority vote.
However, it is still unclear whether the USA will extend the deal.
Tillerson said that in reaching a decision on what the policy should be, the United States must take into account "the totality of the Iranian threat".
Trump, in an interview with the Wall Street Journal, said he is inclined not to certify Iranian compliance after having twice found it compliant at earlier deadlines.
Trump has also set up a team of his White House confidants to present him with "options" other than certifying Iranian compliance with the deal to the Congress.
The nuclear non-proliferation experts said they "firmly support vigorous efforts to monitor and enforce compliance" with the agreement.
Sherman warned against decertification, saying it would rob the USA of any leverage against Iran, drive a wedge between the US and its European allies, undermine American credibility in other negotiations such as on North Korea and NAFTA, and empower hardliners in Iran.
But with Trump having recently sent less-than-subtle signals that he aims to ditch the agreement, those who played an outsize role in brokering it were issuing dire warnings about what that would mean for both USA credibility and regional stability. "This is Israel's position", Netanyahu said from Argentina, where he is on a Latin American swing before making his way to NY for the world body's confab.
"Iran is subject to the world's most robust nuclear verification regime".
But first Trump must decide to extend sanctions relief to Iran under a separate clock.
Only under those circumstances could the US get countries such as China and Russian Federation to abide by them.
In addition, "sanctions never stopped Iran's nuclear program", argued Sherman, saying that the number of Iranian centrifuges grew to 19,000 under the old sanctions regime despite its crippling effect on the Iranian economy.