(Bloomberg) -- U.S. Secretary of State Michael Pompeo made scant progress persuading European Union counterparts to take a harder line toward Iran during a quick visit to Brussels, with the EU standing behind the nuclear accord abandoned by Washington -- and warning of a potential military conflict.

Pompeo presented what the U.S. says is fresh intelligence on the threat posed by Iran in a meeting with counterparts from the three EU nations that joined the landmark 2015 accord that President Donald Trump abandoned a year ago. The top U.S. diplomat received a cool initial response to the surprise visit as foreign ministers from the 28-member bloc convened in the Belgian capital.

“I confirm my worry about the risks of an escalation in a region that definitely doesn’t need further elements of destabilization and tensions,” European Union foreign-policy chief Federica Mogherini told reporters after the meetings. “Our call is to show maximum restraint from all sides.”

As alarm in European capitals grows at Trump’s hard-line approach in the region, there was no appreciable movement in the talks with Pompeo. The U.S. stance has left European allies irritated at the lack of strategy and powerless to sway an American administration that’s failed to provide answers on where it all leads, according to diplomats in Berlin, Paris and London.

“We’ll see what happens with Iran. If they do anything it’ll be a very bad mistake,” Trump told reporters at the White House on Monday. “If they do anything they will suffer greatly."

The State Department’s top envoy for Iran, Brian Hook, described the visit as a “signals check” aimed at sharing intelligence with European allies and not a trip aimed at getting Europe to change its position.

“The secretary wanted to give people an update on the current threat streams that we have been analyzing and to stay in close sync with them,” Hook told reporters after the meetings on Monday. “The developments warrant sharing more information and this was a very good and convenient opportunity.”

Foremost among European concerns is the risk of a return to a nuclear threat in the Middle East, diplomats said on condition of anonymity as talks proceed behind closed doors. The Europeans are in a bind, with limited options to protect the deal.

Pompeo gave his European counterparts little time to prepare on Monday as ad-hoc meetings were scheduled individually. The other 25 member states were left out as Pompeo met with Mogherini, German Foreign Minister Heiko Maas, British Foreign Secretary Jeremy Hunt and France’s Jean-Yves Le Drian.

Looming over the shuttle diplomacy lies a sense that more than 15 years of heavy lifting that culminated in the nuclear deal is slipping away, according to senior European diplomats. And even if few expect an open conflict in the near term, the fear is that Trump’s unpredictable approach could have unintended consequences.

Hook again urged Iran to come to the negotiating table, and said the U.S. approach of maintaining economic pressure, diplomatic isolation and the threat of military force was the best way to compel Iran to change its behavior.

“We believe that Iran should try talks instead of threats,” Hook said. “They have chosen poorly by focusing on threats.”

Regional tensions were laid bare Monday as Saudi Arabia said two of its oil tankers were attacked while sailing toward the Persian Gulf. In one of the incidents an unknown object tore a hole into the hull of a tanker off the coast of the United Arab Emirates.

While Saudi Arabia didn’t directly accuse Iran, the incident adds to a febrile atmosphere in the world’s most important chokepoint for oil shipments as Trump dials up the pressure. Crude rose as much as 2%.

To contact the reporters on this story: Patrick Donahue in Berlin at pdonahue1@bloomberg.net;Jonathan Stearns in Brussels at jstearns2@bloomberg.net;Nick Wadhams in Brussels at nwadhams@bloomberg.net

To contact the editors responsible for this story: Ben Sills at bsills@bloomberg.net, Larry Liebert, Bill Faries

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