Earlier today ne US Secretary of State, Mike Pompeo, presented this administration's "Plan B" at the Heritage Foundation on how to deal with Iran following the US's withdrawal from the nuclear deal, the JCPOA. Pompeo presented 12 demands and threatened to impose "the strongest economic sanctions in history." The Trump administration may wish to do the latter, but the refusal of all the other parties to the JCPOA to go along with this effort will certainly guarantee that even if the sanctions are strong, they will not match what preceded the negotiation of the JCPOA. As it is, Jeffrey Sachs (as reported by Juan Cole) has argued that if Trump tries to sanction European companies dealing with Iran through non-dollar currencies, the EU should take the US to the WTO as well as the UN Security Council and General Assembly. After all, this extraterritorial action would violate international trade agreements, and given that the JCPOA is an officially recognized agreement by the UN Security Council, the US is in fact in violation of international law with its withdrawal, not that those supporting this recognize this.
As it is, the 12 demands are chock full of hypocrisy and nonsense, some of it unacceptable even to a government that would be secular and pro-US. I shall not go through all of them, but will note just three that will not be accepted by Iran, to the extent the are even possible to be carried out. One is for Iran to "cease threatening its neighbors." Well, the problem with this is that it is largely in the minds of such neighbors as Saudi Arabia and UAE that Iran is "threatening" them. KSA has the third highest level of military spending in the world, but somehow Iran is "threatening" it. KSA has called for the military overthrow of the Iranian government. I am unaware of the Iranian government doing the same regarding KSA. Of course many of the demands involve Iraq and Syria, but last time I checked the governments of those nations have invited what Iranian military units are in their nations, with them in Syria battling against rebels backed by KSA and UAE attempting to overthrow that government. Really, this is just ridiculous, although Bahrain might have a complaint about Iran providing some military aid to majority Shia elements in that nation opposed to its dominant Sunni government, but Bahrain has had a problem with this for a long time.
Another is for Iran to stop providing military aid to the "Huthis" in Yemen. Yikes! While KSA and US and UAE have loudly claimed Iran is arming the Houthis, most sources say that most of their arms are US ones. The one thing they may have gotten from Iran are their missiles they have fired off periodically into KSA. Certainly KSA is unhappy about this, but none of these has caused any damage or injuries so far. In contrast, the Saudis with support from the US (and also UAE) have been massively bombing and embargoing Yemen for several years, with thousands killed and famine and cholera endemic in poverty-stricken Yemen. Really, it is the Yemenis who have grounds to be making demands here, in contrast to the US and its allies.
Finally we have a demand to halt (forever) all uranium enrichment. It is clearly the case that what uranium enrichment Iran is engaging in is for its civilian reactor program, which is allowed to Iran, not only under the JCPOA, but also the Nuclear Non-Proliferation Treaty, of which Iran is not only a signatory, but in good standing, with the IAEA saying they are in conformance with it, as well as the JCPOA. As it is, while pursuing nuclear weapons and various foreign activities are not popular in Iran, the civilian nuclear program is and has been highly popular in Iran. It was popular with the dissident Green movement in 2009, and no democratically elected government would shut it down. This demand will only be accepted by a government installed after an invasion by the US and its allies, which this set of demands may be the prelude to.