France’s foreign minister warned on Wednesday that if world powers were unable to quickly reach a new agreement with Iran over its contested nuclear programme then a military confrontation seemed “almost inevitable”.

Speaking after President Emmanuel Macron convened a rare and undisclosed meeting of key ministers and experts on Wednesday to discuss the Iran dossier, Jean-Noel Barrot appeared to ramp up the pressure on Tehran.

European powers are seeking to create a diplomatic path with a view to getting an agreement to curb Iran’s uranium enrichment activity by the summer and ahead of an October 2025 deadline, when U.N. sanctions related to a 2015 accord on Iran’s nuclear programme with world powers expire.

Western powers say the nuclear programme amounts to a disguised effort to develop an atomic bomb. Iran has long denied seeking nuclear weapons.

“The window of opportunity is narrow. We only have a few months until the expiration of this (2015) accord. In case of failure, a military confrontation would seem to be almost inevitable,” Barrot told a parliamentary hearing.

The earlier cabinet meeting, confirmed by three diplomatic sources, is rare and highlights mounting concern among Washington’s European allies that the United States and Israel could launch airstrikes on Iran’s nuclear facilities unless there is a quick negotiated deal on its nuclear programme.

The U.S. has reinforced military capabilities in the Middle East with more warplanes, the Pentagon said on Tuesday, amid a U.S. bombing campaign against the Houthis who control much of Yemen and are supported by Iran.

A senior European official said European strategists were asking themselves whether the campaign could be a precursor to a U.S. strike on Iran in the coming months.

Trump, who has urged Supreme Leader Ayatollah Ali Khamenei to engage immediately in negotiations, threatened Iran on Sunday with bombing and secondary tariffs if it did not come to an agreement over its nuclear programme.

The foreign minister of Iran’s direct adversary Israel will be in Paris on Thursday.

Diplomatic sources said ministers from France, Britain and Germany, all party to the 2015 deal, were hoping to discuss the Iran dossier with U.S. Secretary of State Marco Rubio when they convene in Brussels for a NATO ministerial meeting this week.

Trump withdrew the U.S. from the 2015 deal that placed strict limits on Tehran’s nuclear activities in exchange for sanctions relief.

Since then, Iran has far surpassed that deal’s limits on uranium enrichment, producing stocks at a high level of fissile purity, well above what Western powers say is justifiable for a civilian energy programme and close to that required for nuclear warheads.

The European powers have sought to raise pressure on Iran to coax it back into nuclear discussions. They have held several rounds of talks with Iran including at technical level last week, to try to lay the groundwork.

But the Trump administration has focused initially on a campaign of “maximum pressure”, and the Europeans have found coordination complicated, diplomats say.

The European powers, who can invoke a return of full UN sanctions before October, had hoped to convince Iran to begin negotiating new restrictions on its nuclear activities with a view to having a deal by August at the latest.

That would give enough time to set new limits for Iran’s programme and begin lifting sanctions before the 2015 accord expires in October 2025.