WASHINGTON — US President Donald Trump warned Iran on Thursday that it must reach a deal over its nuclear program or “bad things” will happen, and appeared to set a 10-15 day deadline before the US might take action.

Amid a massive US military buildup in the Middle East that has fueled fears of a wider war, Trump said negotiations with Iran were going well but insisted Tehran has to reach a “meaningful” agreement.

Trump has repeatedly threatened military action against Iran, at first over a deadly crackdown on anti-regime protesters last month that killed thousands, then more recently over its nuclear program. But he has refrained from setting a hard deadline for taking action.

Recalling the US strikes on Iran’s nuclear facilities in June during his remarks at the inaugural meeting of the Board of Peace, his initiative to secure stability in Gaza, Trump said, “Now, we may have to take it a step further — or we may not. Maybe we’re going to make a deal.”

“You’re going to be finding out over the next, probably 10 days,” Trump said.

Trump reiterated that Iran “can’t have a nuclear weapon.”

“You can’t have peace in the Middle East if they have a nuclear weapon,” he said.

“Now is the time for Iran to join us on a path that will complete what we’re doing,” Trump said.

“If they join us, that’ll be great. If they don’t join us, that’ll be great too. But it’ll be a very different path,” he continued. “They cannot continue to threaten the stability of the entire region.”

“They must make a deal. If that doesn’t happen… bad things will happen,” he added.

Later, speaking to reporters aboard Air Force One, Trump was asked about his deadline.

“I would think that would be enough time — 10, 15 days, pretty much maximum.”

“We’re either going to get a deal, or it’s going to be unfortunate for them,” Trump said.

Iran, which vows to destroy Israel, has resisted making major concessions on its nuclear program, which it insists is for peaceful purposes. However, it has enriched uranium to levels that have no civilian use and prevented United Nations atomic agency monitors from accessing some of its facilities. The US and Israel accuse Tehran of trying to develop a nuclear bomb.

Trump’s comments came shortly after Prime Minister Benjamin Netanyahu issued his own warning to Iran, saying, “If the ayatollahs make a mistake and attack us, they will receive a response they cannot even imagine.”

Israel is preparing for a hypothetical scenario in which Iran may attack Israel first amid the ongoing tensions between Tehran and the United States, the Kan public broadcaster reported.

The report did not cite any sources nor provide any further information as to why such a scenario would play out.

Kan did, however, cite Israeli security sources as saying that if Iran follows through on its threat to attack Israel in response to an American assault, Israel will also launch strikes on Iran — something that Israeli leaders have repeatedly publicly said.

Since January, the IDF has been on high alert and has carried out various preparations after Trump threatened military action against Iran against the backdrop of the regime’s killing of protesters.

Preparations have largely focused on the military’s air defense array, attack plans, intelligence, and the Home Front Command, according to the IDF.

The level of preparedness in the military is similar to that ahead of June 2025’s 12-day war with Iran, Kan reported, also without citing any sources. Israel launched strikes on Iranian nuclear sites, saying Iran had taken steps towards nuclear weaponization. Iran responded with missile barrages at Israeli military sites and cities. The US hit Iran on the last day of the war, then brokered a ceasefire

Earlier on Thursday, Russia warned against an “unprecedented escalation of tension” around Iran and urged restraint amid the US military buildup in the region, which a senior American official said should be complete by mid-March.

Trump has sent aircraft carriers, warships, and jets to the region, raising the prospect of another attack on the Islamic Republic. Hebrew media outlets reported that a US Air Force plane, used to command special forces operations, landed at Ben Gurion Airport near Tel Aviv on Thursday.

Washington wants Iran to entirely give up uranium enrichment, a process used to create fuel for atomic power plants but that can also provide material for a warhead.

The US and its ally Israel also want Iran to give up long-range ballistic missiles, stop supporting proxy militias around the Middle East, and stop using force to quell internal protests.

Iran says it refuses to discuss issues beyond the atomic file, calling efforts to limit its missile arsenal a red line.

Satellite pictures have tracked both Iranian work to repair and fortify sites since last summer, showing work at both nuclear and missile sites, as well as preparations at US bases across the Middle East over the past month.

Iranian and US negotiators met on Tuesday, and Iranian Foreign Minister Abbas Araghchi said they had agreed on “guiding principles.” White House press secretary Karoline Leavitt said on Wednesday, however, that the two sides remained apart on some issues.

In a sign of growing concern over the increased tensions, Poland on Thursday became the latest European country to urge its citizens to leave Iran, with Prime Minister Donald Tusk saying Poles may only have hours to evacuate.

Germany, meanwhile, moved troops out of northern Iraq, reducing its footprint to the minimum necessary to keep its base there functional, citing regional tensions.

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Iran's nuclear program

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