How advanced is Iran’s nuclear program? Here’s what we know as U.S. and Israel launch strikes.

Washington — President Trump ordered military strikes against Iran Saturday morning, after pressuring the country to scale back its nuclear program, grappling with an issue that has vexed presidents of both parties for decades.

Iran – which denies having nuclear ambitions – has accumulated a stockpile of uranium enriched to the level of purity needed to build a bomb. Mr. Trump ordered strikes on three key Iranian nuclear sites last June, causing significant damage and leaving the status of stockpiles uncertain. Today, less than a year later, the president is leading what could be a broader military campaign.

‘We will make sure Iran does not get a nuclear weapon,’ Mr Trump said in a video Saturday morning announcing what he called a “massive, ongoing operation.” He said he had “repeatedly sought to reach a deal” but Iranian officials “rejected any opportunity to give up their nuclear ambitions, and we can’t take it anymore.”

The United States and Iran had engaged in several rounds of indirect negotiations in recent weeks, as a fleet of U.S. warships and military aircraft arrived in the Middle East to increase pressure.

Here are some details about Iran’s nuclear program:

Is Iran on the verge of building a nuclear weapon, and is it currently building one?

In recent years, Iran has rapidly increased its stockpiles of highly enriched uranium. By mid-June 2025, shortly before the U.S. strikes that month, Iran had enriched some 972 pounds of uranium to 60 percent purity, according to estimates by the International Atomic Energy Agency.

For comparison, Iran had 605.8 pounds of 60% enriched uranium in February 2025, and 267.9 pounds a year before, the IAEA said. According to the UN monitoring body metricabout 92.5 pounds of 60% enriched uranium is enough to build a single nuclear weapon if enriched further.

This material is only a small step far from weapons-grade uranium enriched to 90%.

The US Defense Intelligence Agency estimated last May that it would “probably take less than a week” for Iran to produce enough weapons-grade uranium to make its first bomb, if it decided to do so. In reality, building a bomb might take a little longer: another roundup of last year’s intelligence found that Iran could build a nuclear device within three to eight months unless it faces technical or logistical delays, CBS News previously reported.

What is unclear, however, is whether Iran made the decision to build nuclear weapons. Iran would have stopped its nuclear weapons program in 2003, and the U.S. intelligence community estimated last spring that the program had not restarted.

“Iran almost certainly does not produce nuclear weapons, but Iran has undertaken activities in recent years that put it in a better position to produce them, if it chooses to do so,” the DIA said in May.

Asked on Feb. 18 whether the U.N. International Atomic Energy Agency had seen indications that Iran may currently be working to develop a nuclear weapon, the agency’s director general Rafael Grossi said this was not the case for a French television channel.

“No,” he told TF1, adding: “On the contrary, today I see a desire on both sides to reach an agreement,” referring to the United States and Iran.

Iran, for its part, has long insisted that its nuclear program is entirely peaceful and that it does not intend develop a nuclear weapon.

Iran’s stockpile includes uranium enriched well beyond the level needed for most non-military uses such as nuclear power or medical applications. The IAEA said in May that Iran was now “the only non-nuclear-weapon state producing such nuclear materials.”

What was the impact of the latest US strikes against Iran?

The airstrikes of last June target Iran’s Fordo and Natanz enrichment facilities and a research site near the city of Isfahan. It is unclear to what extent these strikes damaged Iran’s nuclear program.

Mr. Trump has long claimed that the strikes “obliterated” the three nuclear sites, move back the program by “essentially decades”.

Grossi from the IAEA told CBS News in June, that the strikes had caused “serious damage” but not “total damage”.

In his interview with the French network in February, Grossi said that Iranian nuclear materials were “still there, in large quantities,” despite the U.S. strikes, although “some of them might be less accessible.”

Iran is also not currently enriching uranium, Secretary of State Marco Rubio told reporters on February 25, while asserting that “they are trying to get to the point where they can eventually do that.”

Satellite images dating from late January show roofs constructed on damaged buildings at the Natanz and Isfahan sites, which could indicate Iran’s efforts to salvage remaining materials.

A confidential report released by the IAEA estimates that Iran is carrying out unexplained activities at nuclear sites bombed by the United States, CBS News has confirmed.

The IAEA says it withdrew its inspectors from Iran for security reasons shortly after the June strikes, and Iran decided to suspend cooperation with the agency the following month. The agency said in November that it was able to conduct some inspections in the months after the attacks, but not at any of the sites struck by U.S. forces.

Iran has downplayed the strikes, argue they did not eliminate its technological capabilities.

“Yes, you destroyed the facilities, the machines,” Iranian Foreign Minister Abbas Araghchi said on Fox News in January. “But technology cannot be bombed, and determination cannot be bombed either.”

What is the history of Iran’s nuclear program?

Iran’s nuclear program dates back several decades, with some early research activities conducted under the United States-allied government that controlled the country before the 1979 Islamic Revolution. In the mid-1980s, Iran began developing – or buy on the black market — the technology necessary to build centrifuges capable of enriching uranium, according to the IAEA.

The country’s ambitions sparked intense international pressure starting in 2002, when an anti-regime group claimed that Iran had secretly built two nuclear facilities. The administration of former President George W. Bush later alleged that Iran was working to develop missiles capable of delivering nuclear weapons.

The IAEA said that until 2003, Iran had a “structured program” to carry out “activities relevant to the development of a nuclear explosive device.” The agency added that some of these activities have military and non-military uses, but some “are specific to nuclear weapons.”

While U.S. intelligence officials believe Iran stopped trying to develop nuclear weapons in 2003, the country resumed uranium enrichment several times afterward. As a result, he faced years of increasingly harsh sanctions.

In 2015, President Barack Obama’s administration reached a deal with Iran and other world powers to limit the country’s uranium stockpiles and enrichment capacity for a specified period and to subject Iran’s nuclear program to IAEA oversight, in exchange for sanctions relief. The agreement was known as the Joint Comprehensive Plan of Action, or JCPOA.

Three years later, Mr. Trump unilaterally withdrew the United States from this agreementwhich, according to him, was insufficient. He imposed a new round of tough sanctions, calling it a “maximum pressure” campaign aimed at forcing Iran to negotiate a new deal. Efforts by the Biden administration and the European parties to the JCPOA to restart the agreement have failed.

Since then, Iran has ceased to respect the terms of this agreement and has considerably accelerated its uranium enrichment program, notably by uranium enrichment at 60% purity for the first time.

At times, Mr. Trump has pushed Iran to abandon uranium enrichment altogether, rather than stick to lower enrichment levels in order to support a civilian nuclear program.

“They want to enrich a little bit. You don’t have to enrich when you have so much oil,” the president said on February 27. “I say, no enrichment.”

Araghchi dismissed the idea, calling the enrichment program “a matter of dignity and pride.”

“We have every right to benefit from peaceful nuclear energy, including enrichment,” he told CBS News in a statement. Interview of February 22. “As a sovereign country, we have every right to decide for ourselves. We developed this technology by ourselves, by our scientists, and it is very dear to us, because we paid a lot.”