Russian President Vladimir Putin listens to his French counterpart Emmanuel Macron make a statement in St. Petersburg, Russia on May 24, 2018. Tobias Schwarz / Reuters

Nearly one year after hosting Russian President Vladimir Putin at Versailles, French President Emmanuel Macron went to St. Petersburg. The French leader, who is addressing the St. Petersburg International Economic Forum Friday, held direct talks with his Russian counterpart Thursday, during which the two discussed the crisis in Ukraine, the war in Syria, and, perhaps most pressingly, how to salvage the Iran nuclear deal both France and Russia are party to.

Such a visit would have been awkward just two months ago. At that time, tensions between Moscow and Europe had reached Cold War-era heights after a former Russian spy was poisoned with a rare nerve agent on British soil—the kind of attack the U.K. and its allies alleged only Russia could have pulled off, despite repeated denials from Moscow. The row ultimately resulted in the expulsion of more than 100 Russian diplomats from capitals across Europe and North America. Russia issued tit-for-tat expulsions in response.

But that was then—this is now. President Trump’s recent decision to withdraw the U.S. from the Joint Comprehensive Plan of Action (JCPOA), as the Iran deal is formally known, has put Europe between a rock and a hard place. On one hand, it could resign itself to watching its signature diplomatic achievement crumble. On the other, it could attempt to salvage the deal, even if it means exposing its businesses to U.S. sanctions. So far, European leaders appear to have opted for the latter, committing themselves to maintaining the agreement, even if it means doing so without Washington. “As long as the Iranians respect their commitments, the EU will of course stick to the agreement of which it was an architect,” European Commission President Jean-Claude Juncker said last week, adding that the bloc will “do what we can to protect our European businesses” from U.S. sanctions penalizing companies that do business with Iran. This includes introducing regulations that would prevent European companies from complying with the sanctions (but as my colleague Krishnadev Calamur points out, it’s not entirely clear how effective they will be).

Tehran has already raised alarm this week over European firms pulling back business from Iran, making Macron and Putin’s meeting all the more crucial. As one of the six remaining signatories to the deal (China, France, Germany, the U.K., and Iran are the others), Russia shares the EU’s goal of keeping the nuclear agreement alive. We have never supported the policy of unilateral sanctions and will never do that as we believe them to be illegal,” Maria Zakharova, Russia’s foreign ministry spokesperson, said on Wednesday in apparent reference to the reimposition of U.S. sanctions on Iran. “We are determined to advance our comprehensive cooperation with Iran.”

Trump’s decision to withdraw the U.S. from the Iran deal adds another crack in the relationship between Washington and its European allies—after those caused by the U.S.’s withdrawal last year from the Paris climate accord and Trump’s more recent threat to impose steep aluminum and steel tariffs on the European Union (waivers for which expire next week). These diplomatic fissures have prompted some to question the durability of the trans-Atlantic relationship. On Iran, at least, there’s a risk of Europe drifting further from the U.S. and closer to Russia.

Though Europe and Russia now find themselves on the same side of the Iran deal issue—opposite the U.S.—it’s still a far cry from complete rapprochement. “It’s short-term, circumstantial community of interest,” Mathieu Boulègue, a research fellow focusing on Russia and Eurasia at the London-based Chatham House, told me. Not only have Europe and Russia backed opposing sides in the ongoing war in Syria, but Europe also, along with the U.S., continues to impose heavy sanctions on Moscow over its annexation of Crimea in 2014.

And Macron has been vocal about these differences. During his and Putin’s first meeting in Versailles last year, he famously took the opportunity to deride Russian state media outlets Russia Today and Sputnik as “agents of influence and propaganda.”

But Boulègue said these differences shouldn’t compromise Russian-European cooperation when it comes to Iran. “This is the core of diplomacy,” he said, adding: “It’s not because you’re not friends on one issue that you cannot be friends on another.”

In a joint press conference following their meeting Thursday, Macron put the emphasis on France and Russia’s mutual interests, as well as their historic and cultural ties. “We are quite aware that we have allowed some misunderstanding of our mutual relationships,” Macron said, adding that both sides should move forward together and “keep working on strengthening our mutual trust.”

Despite their differences, they do have another important thing in common: A willingness to stand up to—or, depending on your perspective, stick it to—the United States. “Russia will exploit as much as possible this narrative that the United States is not respecting its international engagements,” Boulègue said. “It will be presented as a victory and this will allow Russia to have an upper hand in any future negotiations with regards to Iran, and that is directly linked to Syria because Iran is indeed a key player in any sort of peace settlement in Syria. … Russia will definitely capitalize on that.”

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