Bridging the Atlantic to Counter Tehran

President Donald Trump’s return to the White House has startled many allies, with concerns ranging from tariff threats against Europe to pressuring Denmark to sell Greenland and arguing with Zelensky in the oval office. Fortunately, discord need not be everywhere.

Trump’s return offers a unique opportunity for a more united trans-Atlantic Iran policy that addresses Tehran’s fast-widening threat radius.

Over the past four years, the EU and UK have steadily embraced their own – admittedly lighter – version of “maximum pressure” against Tehran. No doubt, this was triggered by Iran’s increasing enriched uranium output, ballistic missile attacks against Israel, crackdown against nationwide anti-regime protest, and transfer of drones and missiles to Russia for use against Ukraine.

There have even been times when London, Paris, and Berlin sprinted ahead, seeking to impose greater diplomatic pressure to check Tehran’s nuclear escalation when Washington counseled restraint.

This change is welcome and should be built upon. For more than three decades, Europe pursued a failed and conciliatory approach toward Tehran, hoping to moderate the regime’s behavior through dialogue and economic and political enmeshment. In response, the Islamic Republic pocketed concessions and exploited goodwill to advance its nuclear program, expand its missile arsenal which threatens the European continent, and fuel conflicts across the Middle East with significant global ramifications.

Examples of the latter include Tehran’s material support for the Assad regime’s crackdown on protestors, which led to a decade-long migration crisis; and more recently, the Houthi campaign against maritime traffic in the Red Sea, which led to increased prices for Western consumers as well as shipping and insurance spikes.

Only by developing a united playbook to counter the breadth and depth of the threat posed to the West from Tehran’s terrorists and theocrats can a more effective, strategically sound, and morally coherent policy emerge from the European continent.

The first lesson is that pressure can compel Iran’s most powerful person, currently, Supreme Leader Ali Khamenei, to retreat or back down. History is replete with examples of this.

The Islamic Republic’s “founding father” and first Supreme Leader, Ayatollah Ruhollah Khomeini, was forced to accept a UN-sponsored ceasefire to end the bloody eight-year Iran-Iraq War despite seeking regime change in Baghdad for nearly seven and a half years.

In term one of the Trump administration, Iranian officials exclaimed that U.S. unilateral oil sanctions – measures which Europe opposed and fought against – were more painful and costly than the entire Iran-Iraq War.

Rather than allow Tehran to again take advantage of another potential trans-Atlantic riff, policymakers across the EU and UK should work with the new administration to leave Khamenei with no other option than submission. Here’s how:

First, the UK, France, and Germany should develop a roadmap with the new administration for utilizing the “snapback” mechanism enshrined in Security Council Resolution 2231 to re-impose multilateral sanctions on Iran. This mechanism expires on October 18, and with it, the ability to use the Security Council against the regime in the future given deepening Russo-Iranian ties.

Second, the Brussels and London should proscribe Iran’s Islamic Revolutionary Guard Corps (IRGC) in its entirety as a terrorist organization. The IRGC is the regime’s primary instrument engaging in terrorism and suppressing dissent. The IRGC has been behind several foiled plots across Europe. Not only would sanctioning the IRGC support existing law enforcement measures, but it would send a powerful message to the Iranian people and diaspora.

As a corollary, the EU and UK should never miss an opportunity to use the bully pulpit against the regime’s human rights violations and continue to ratchet up sanctions to name, shame, and punish those who engage in these abuses.

Third, Europe should end Tehran’s hostage diplomacy. Seizing foreign citizens and dual nationals offers Iran political leverage and financial gain. By implementing preemptive measures to protect its citizens, policymakers can deter this practice. Such measures can include expelling Iranian embassy workers and regime officials, banning travel to Iran, and shuttering Western embassies in Iran and Iranian embassies across Europe until the hostage-for-cash scheme ends.

Fourthly, building off of the closure of the Hamburg Mosque, which was tied to Iran’s Lebanese proxy Hezbollah, Iran-backed cultural and religious centers should be shuttered to prevent and hinder espionage, radicalization, and terrorist activities.

Europe should also sanction the Supreme Leader’s Business Network. Khamenei’s vast business empire is worth upwards $200 billion and that allows Tehran to continue to finance terrorism. Sanctioning this network would strike at the heart of the regime’s economic lifeline and send an important political message against the regime’s elites.

Finally, Brussels, London, and other capitals should work with Washington to curb Tehran’s trade with Beijing. China is the largest customer of Iran’s sanctioned oil, which keeps the Islamic Republic afloat financially. Europe can help limit China-Iran trade by identifying and pressuring Chinese entities with an international footprint, such as banks.

Fundamentally, the facts on the ground in 2025 indicate that European strategic interests align more with Washington against Tehran than any other point in the past 46 years of the Islamic Republic’s existence. The question now is, will policymakers across the continent work with Trump to make sure that politics follows suit?

Saeed Ghasseminejad & Behnam Ben Taleblu

Senior Advisor & Senior Director | Foundation for Defense of Democracies