Trump has certified the deal twice, once in April and once in July, although he has said he did not want to do it. Members of Trump's team, including Secretary of State Rex Tillerson and Treasury Secretary Steve Mnuchin, cite Iran's "malign" activity in the region as a violation of the agreement.
If Trump follows through and decertifies the deal on Friday, it will begin a 60-day countdown clock for Congress to decide whether to "snap back" those nuclear sanctions.
But Mr Trump is under pressure both at home and overseas not to scrap the deal. Tom Cotton, R-Arkansas, are wary of decertification because it would constitute a "material breach" of the agreement and could destroy it.
Serious concern has been growing on the possible United States administration's withdrawal from Iran nuclear deal.
"If we pass the message that with every change of administration in Washington or elsewhere deals are thrown away and renegotiated, no one would negotiate with any administration ever and any deal would be exposed to be renegotiated every term".
Several European allies have urged Trump not to nix the agreement, but instead to build on it, possibly addressing "sunset" provisions (by 2026, key nuclear restrictions lift on the accord).
In a rare case of the United Kingdom publicly pressuring the US, the British government said Wednesday that Foreign Secretary Boris Johnson had called Secretary of State Rex Tillerson to underscore British support for the deal. "We may have to array our forces to prepare for. calibrated strikes".
The certification would also demand that the intelligence community produce judgments on a wide range of Iranian behaviour that is not covered by the nuclear deal, including ballistic missile testing and development, support for Lebanon's Hezbollah movement and Syrian President Bashar Assad and threats to Israel and the Mideast more broadly, according to the drafts. That declaration could lead to an unraveling of the seven-nation pact and leave the United States, not Iran, as the country that balked at honoring its commitments.
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"They got a path to nuclear weapons very quickly, and think of this one - $1.7 billion in cash", he said, in reference to a decision by the Obama administration to settle a decades-long legal claim with Iran as part of the deal.
"There is no technical nor political space to renegotiate this deal", Federica Mogherini, the EU's High Representative for Foreign Affairs and Security Policy, told PBS Wednesday. But again, none of that is likely since the USA would be essentially tearing up the agreement and taking the blame for whatever comes next.
Even so, some experts told CNBC that decertification will undermine the worldwide deal and encourage hardliners in Tehran to push for nuclear weapons.
Engel said the United States would lose any leverage it has with allies in the deal if it abandons the JCPOA. If any points of the agreement are violated by Iran, sanctions against the country will be renewed.
After Trump made clear three months ago he would not certify Iran's compliance with the deal, his advisers moved to give him options to consider, a senior administration official said. "It doesn't try and do more. that needs to be understood and recognised in Washington".
She said that U.S. would lose global trust "because a deal that America voted for just two years ago in the UN Security Council with a resolution unanimously adopted, a deal that America helped to shape enormously, enormously, would be rejected by the same country".
What exactly that will look like is still being determined, but it could include greater congressional oversight.