Addressing the U.S. conflict with Iran on Wednesday, Mr. Trump called on Europeans to abandon the 2015 Iran nuclear deal, as he did in May 2018. His wish is likely to go unheeded.

Just a few hours before the president spoke, top European leaders repeated their commitment to the deal and urged Iran to return to compliance, even in the face of harsh American sanctions.

After the killing of General Suleimani, Iran announced that it no longer would be limited by the deal, but it did not say what it would do, leaving room for both escalation and a return to compliance.

The European Commission President, Ursula von der Leyen, and the bloc’s foreign policy chief, Josep Borrell Fontelles, both said the nuclear agreement should be preserved. To that end, Ms. von der Leyen, said Mr. Borrell has been reaching out to all signatories to the deal, including Russia and China.

Iran has, in effect, been making a phased retreat from its obligations under the deal since Mr. Trump abandoned it and reimposed economic sanctions on Iran.

Britain, France and Germany, together with the European Union, Russia, China and the United States negotiated the deal, but only Washington has pulled out of it. Iran has regularly complained that the Europeans are not doing enough to provide Iran the economic benefits it was promised in the deal.

Any country giving Iran financial assistance could run afoul of the sanctions and risk incurring sanctions itself. But both Russia and China have found ways to buy at least some Iranian oil. And some European countries have proposed workarounds to help Iran while complying with U.S. policy.