Officials familiar with the internal deliberations as well as informed sources outside the administration say they expect Mr Trump to tell lawmakers that the Iran deal is not in the USA national security interest despite Iran's technical compliance.
Political observers have warned that any unilateral action by the United States based on unsupported claims of Iranian non-compliance would isolate Washington, impede future efforts for other nonproliferation agreements in the broader global community and increase the likelihood of a wider conflict in the Middle East. That could include sanctioning Iran's Revolutionary Guard Corps as a terrorist organization or trying to cripple the country's ballistic missile program with more sanctions, two sources told ABC News.
Under the 2015 deal, Tehran agreed to roll back its nuclear program in exchange for relief from wide-ranging oil, trade and financial sanctions that had choked the Iranian economy. Trump is expected to declare that the deal is not in America's national interest.
It also would indicate that the United States would be willing to renegotiate agreements with every new administration, giving other countries reason to hesitate on negotiations if they felt future leadership would give them a better deal, Mogherini added.
"The decertification is an essential first step to persuading the Europeans that the alternatives to fixing the deal could be President Trump's decision to abandon the deal", said Mark Dubowitz, CEO of the Foundation for Defense of Democracies, a nonpartisan policy institute.
After failing to make Trump change his mind, European diplomats and businessmen have shifted the focus of their lobbying efforts on US Congress to help prevent Washington from killing the JCPOA. Engel, the top Democrat on the Foreign Affairs Committee, said unwinding the agreement would send a unsafe signal to allies and adversaries alike.
After de-certification, the U.S. Congress will review - in a process that will take 60 days - whether it is time to re-apply U.S. sanctions on Iran that were suspended after the JCPOA was signed.
Last month, Trump, during an address before the United Nations General Assembly, said, "The Iran deal was one of the worst and most one-sided transactions the United States has ever entered into frankly that deal is an embarrassment to the United States, and I don't think you've heard the last of it".
Watch Federica Mogherini's full interview with the NewsHour's Judy Woodruff on Wednesday. Instead, these officials said Trump is more inclined to push legislators to amend the law that requires the president to certify Iran's compliance every 90 days. If those sanctions are put back into place, the JCPOA would be considered breached. The IAEA certified in its latest quarterly report on August 31, 2017, that Iran has complied with the JCPOA and that its stock of low-enriched uranium and centrifuges for enrichment are in line with the nuclear pact.
"Congress and the administration need to be on the same page, and a major breakdown in the working relationship between one of the very few key Republicans on the Hill who works with Democrats and the president on Iran policy bodes very poorly", said Elizabeth Rosenberg, a former Treasury Department official now at the Center for a New American Security. But again, none of that is likely since the US would be essentially tearing up the agreement and taking the blame for whatever comes next.
What exactly that will look like is still being determined, but it could include greater congressional oversight.