On Thursday, the United Nations Panel of Experts released a 329-page report detailing the evidence behind recent accusations levied against the Islamic Republic of Iran regarding its provision of advanced weapons to regional proxies, in violation of UN sanctions. The document was eagerly welcomed by Nikki Haley, the US ambassador to the international body, who said that it corroborated much of what the White House has been saying about Iranian misbehavior for several months.

The report follows upon an earlier statement by UN Secretary General Antonio Guterres, which similarly affirmed that Tehran was, at a minimum, failing to prevent its weapons from falling into the hands of groups like the Houthi rebels in Yemen. While Iran affirms political support for that Shiite militant group, it denies having provided arms shipments or other forms of direct support. However, several weapons caches have been intercepted since the outbreak of the Yemeni Civil War while apparently en route between Iran and Houthi-controlled ports. Additionally, Iran’s adversaries continue to accuse the Islamic Republic of even more direct participation in the conflict, including through the deployment of advisers from the Revolutionary Guards.

In recent weeks, the US has touted evidence of Iranian involvement in the form of missile components recovered from Saudi Arabia after being fired into that country from Houthi territory. In a press conference last month, Ms. Haley described that material as various clear signs of Iranian manufacture and design. Much of this information was confirmed by the UN report, which in turn reignited American calls for action both over Iran’s role in the broader Middle East and regarding the ballistic missile program that Iranian officials have repeatedly refused to constrain in any way.

Many critics of the Iranian regime maintain that this refusal is in violation of the UN Security Council resolution governing the implementation of the 2015 Iran nuclear deal. As the Joint Comprehensive Plan of Action failed to address concerns over the development of missiles that could potentially carry a nuclear warhead, this issue was taken up in UNSC Resolution 2231, which calls upon the Islamic Republic to avoid work on all such weapons. Yet Iran and its allies have continued to insist that it is not obligated to comply with this provision.

“The world cannot continue to allow these blatant violations to go unanswered,” Haley said on Friday, according to CBS News. “Iran needs to know that there are consequences for defying the international community. It's time for the Security Council to act.”

These renewed calls for action emerged in parallel with new signs of support from US allies for the effort to tighten restrictions on the Islamic Republic. On Friday, Reuters reported that British Prime Minister Theresa May had commented upon a meeting with German Chancellor Angela Merkel that both leaders remained committed to preserving and fully implementing the JCPOA, and that they “also share the U.S. concerns about Iran's destabilising activity in the Middle East, and… stand ready to take further appropriate measures to tackle these issues.”

There is little doubt that these shared concerns were amplified by the previous weekend’s flare-up between Iran and Israel. The incident began with an Iranian drone’s incursion into Israeli airspace, which led to it being shot down before Israel launched a strike on its point of origin in Syria. Subsequently, one Israeli jet was shot down, though its pilots ejected into Israeli territory, and a dozen other military sites in Syria were destroyed, including four that were reportedly controlled by Iranian forces.

Beyond from the immediate effects of this clash on international dialogue over Middle Eastern affairs, it seems clear that the Israeli government is using it to more urgently call for joint action to constrain Iran’s role in the region. Israeli Prime Minister Benjamin Netanyahu has repeatedly said that his nation will not accept a permanent Iranian presence in Syria, where it would present an intensified threat to the Jewish state, which Tehran has often vowed to destroy.

Netanyahu spoke to the UN Secretary General on Friday and insisted that Israeli forces will “act against it” if Iran continues to develop military bases there. Then, on Sunday, the Israeli Prime Minister warned Iran against “testing Israel’s resolve” while speaking at the Munich Security Conference. According to the Associated Press, Netanyahu’s address was followed two hours later by remarks from Iranian Foreign Minister Javad Zarif, making the event an outlet for dialogue over not just the existing tensions but also their perceived underlying causes, including the Iran nuclear deal.

Time described Netanyahu as saying that that agreement had emboldened the Iranian regime’s activities in the broader Middle East. He went on to suggest that the White House could follow through on threats to scrap the JCPOA with little fear of consequence. Zarif predictably rejected this notion, issuing the vague threat that “people would be sorry for taking the erroneous action.”

By suggesting that the recent clash was a sign of Iran’s perceived impunity following the nuclear negotiations, Netanyahu effectively tied the future of the JCPOA to the potential danger of further such clashes. This may put additional pressure on European policymakers who have until May 12 to arrive at an agreement that would prevent US President Donald Trump from withholding waivers on Iran sanctions, essentially killing the deal. But it remains unclear whether such an agreement is attainable, even in the face of added pressure.

On Sunday, Reuters reported that the State Department had offered a possible way forward in the form of a two-phase process for negotiating with the European signatories to the agreement, namely Britain, Germany and France. Under this plan, the Europeans would initially need only to provide a general commitment to addressing the perceived deficiencies in the JCPOA. Thereafter, the negotiations over how to actually do so would begin only after the May deadline, ideally with input from the other signatories: Iran, Russia, and China.

But the same report specified that despite recent shifts in the direction of the US’s more assertive tone on Iran policies, the relevant European policymakers are still wary about making such a commitment. Reuters cited two European officials and two former US officials as saying the European remain unclear on exactly what the White House’s demands are, and thus are concerned that they may be committing to a plan they will ultimately not be willing to follow through on.

But as much uncertainty as there is about Trump’s final objectives, there is perhaps just as much certainty about what Europe might be willing to commit to in the future. After all, escalating tensions in the Middle East, together with ongoing advocacy efforts by the White House and other Iranian adversaries, have already contributed to a more assertive shift in tone. As these trends continue, the Europeans growing concerns may begin to outweigh their convictions regarding the nuclear deal.