Iran and the United States are sliding rapidly towards military conflict as hopes fade for a diplomatic solution to their standoff over Tehran’s nuclear program, officials on both sides and diplomats across the Gulf and Europe say.

Iran’s Gulf neighbors and its enemy Israel now consider a conflict to be more likely than a settlement, these sources say, with Washington building up one of its biggest military deployments in the region since the invasion of Iraq in 2003.

Israel’s government believes Tehran and Washington are at an impasse and is making preparations for possible joint military action with the United States, though no decision has been made yet on whether to carry out such an operation, said a source familiar with the planning.

It would be the second time the US and Israel have attacked Iran in less than a year, following US and Israeli airstrikes against military and nuclear facilities last June.

Regional officials say oil-producing Gulf countries are preparing for a possible military confrontation that they fear could spin out of control and destabilize the Middle East.

Two Israeli officials told Reuters they believe the gaps between Washington and Tehran are unbridgeable and that the chances of a near‑term military escalation are high.

Some regional officials say Tehran is dangerously miscalculating by holding out for concessions, with US President Donald Trump boxed in by his own military buildup - unable to scale it back without losing face if there is no firm commitment from Iran to abandon its nuclear weapons ambitions.

“Both sides are sticking to their guns,” said Alan Eyre, a former US diplomat and Iran specialist, adding that nothing meaningful can emerge “unless the US and Iran walk back from their red lines - which I don’t think they will.”

“What Trump can’t do is assemble all this military, and then come back with a ‘so‑so’ deal and pull out the military. I think he thinks he’ll lose face,” he said. “If he attacks, it’s going to get ugly quickly.”

Two rounds of Iran-US talks have stalled on core issues, from uranium enrichment to missiles and sanctions relief.

When Omani mediators delivered an envelope from the US side containing missile‑related proposals, Iranian Foreign Minister Abbas Araghchi refused even to open it and returned it, a source familiar with the talks said.

After talks in Geneva on Tuesday, Araghchi said the sides had agreed on “guiding principles,” but the White House said there was still distance between them.

Iran is expected to submit a written proposal in the coming days, a US official said, and Araghchi said on Friday he expected to have a draft counterproposal ready within days.

But Trump, who has sent aircraft carriers, warships and jets to the Middle East, warned Iran on Thursday it must make a deal over its nuclear program or “really bad things” will happen.

He appeared to set a deadline of 10 to 15 days, drawing a threat from Tehran to retaliate against US bases in the region if attacked. The rising tensions have pushed up oil prices.

US officials say Trump has yet to make up his mind about using military force although he acknowledged on Friday that he could order a limited strike to try to force Iran into a deal.

“I guess I can say I am considering that,” he told reporters.

The possible timing of an attack is unclear. US Secretary of State Marco Rubio is due to meet Israeli Prime Minister Benjamin Netanyahu on February 28 to discuss Iran. A senior US official said it would be mid-March before all US forces were in place.