Iran's Chemical Weapons Threat: What Israel Intelligence Reports Reveal

Israel has shared intelligence with the United States claiming that Iran is considering using chemical weapons against its adversaries, including through missiles or by smuggling them into other countries. However, the assessment has divided American officials, with some expressing alarm and others questioning its credibility and whether Tehran would actually authorise such an attack.

According to The New York Times, Israeli intelligence officials told their American counterparts that Iran was advancing technology that could allow it to attach chemical weapons to missiles. They also raised the possibility of Tehran smuggling chemical agents or weapons into Israel and other countries. Israel shared parts of its assessment with Gulf countries, but some regional governments questioned the evidence behind the claims. In Washington, the main disagreement centres on whether Iran's leadership would actually authorise the use of such weapons, particularly if it is not attacked again.

The allegations come amid continuing tensions between the United States and Iran, with both sides exploring diplomatic options while preparing for the possibility of renewed fighting. The dispute over the intelligence has also revived comparisons with the flawed American intelligence assessments about Iraq's weapons of mass destruction before the 2003 invasion.

What Israeli intelligence claims about Iran's chemical weapons

Israeli officials have reportedly presented the chemical weapons threat as more urgent than Iran's nuclear ambitions during recent discussions with American intelligence agencies and other officials. Their assessment suggests Tehran could be advancing the technology required to attach chemical weapons to missiles. The New York Times report also identified drones as another possible means of delivery, although it did not establish that Iran had developed an operational system for such an attack.

The Israeli briefings also raised the possibility that chemical weapons could be smuggled into Israel or other countries.

However, the ability to develop a delivery mechanism does not necessarily mean Iran has a functioning system capable of carrying out an effective chemical weapons attack. According to The New York Times, weapons experts and American officials said mounting a chemical weapon on a ballistic missile was not particularly difficult, but ensuring that the chemical agent dispersed effectively over a target presented a greater challenge. Smuggling a weapon across an international border would also involve operational difficulties.

The Israeli assessment has not received uniform support from Washington or Gulf governments. A regional official told the newspaper that Israeli representatives had presented assessments suggesting Iran was working to make chemical weapons operational but had not provided supporting evidence. The official said Gulf governments regarded the claims as "unserious".

The New York Times reported that there was little debate within the US intelligence community over whether Iran was developing chemical weapons, but significant disagreement over whether its leaders would ever use them, particularly if Tehran was not provoked by further attacks. The distinction between developing such capabilities and deciding to deploy them remains central to the intelligence dispute.

Some American officials have also questioned whether the intelligence is being used to build support for renewed military operations against Iran. Others believe the warnings should be taken seriously, particularly given separate concerns about Iranian preparations to target American interests in the region.

For some American officials, the claims have revived memories of the flawed US intelligence assessments in 2002, which told the White House that Iraq possessed weapons of mass destruction. Iraq had largely abandoned or frozen its nuclear, chemical and biological programmes by then, but the intelligence agencies presented their assessment as ironclad.

Iran's chemical weapons history and the US intelligence assessment

Iran's history with chemical weapons dates back to the 1980–1988 Iran-Iraq War, during which Iraqi forces under Saddam Hussein used chemical agents against Iranian troops and civilians. The attacks killed thousands and left many survivors with long-term health complications. According to Iranian experts cited by The New York Times, approximately 100,000 Iranian veterans and civilians experienced decades of health problems following the chemical attacks.

According to the US State Department, Iran first acknowledged in May 1998 that it had developed a chemical weapons programme during the Iran-Iraq War, claiming it had terminated the programme after the 1988 ceasefire. Iran has since denied possessing chemical weapons and previously described accusations about such capabilities as an Israeli campaign of psychological warfare, according to The New York Times.

Iran is also a signatory to the Chemical Weapons Convention (CWC), which prohibits the development, production, stockpiling and use of chemical weapons. It signed the treaty in 1993 and ratified it in 1997. However, a 2023 US State Department report found Iran in non-compliance with the convention, citing its failure to declare an alleged transfer of chemical weapons to Libya in 1987, incomplete declarations of its chemical weapons production facilities and riot-control agents, and concerns over research into pharmaceutical-based agents and toxins for offensive purposes. These are US government findings and allegations, rather than a new assessment of the Israeli intelligence claims.

Concerns about Iran's research have also appeared in official American intelligence assessments. In its 2025 Annual Threat Assessment, the US intelligence community said Iran "very likely aims to continue R&D of chemical and biological agents for offensive purposes". The assessment also noted that Iranian military scientists had researched chemicals with sedative, dissociative and amnestic incapacitating effects, which can also be lethal.

Dana Stroul, who served as the Pentagon's top Middle East policy official during the Biden administration and is now with the Washington Institute for Near East Policy, said Iran had been known to stockpile components for chemical weapons for more than two decades but had never deployed them. She warned that Tehran could feel "existentially pressured" and potentially cross the line into the direct offensive use of such weapons, according to The New York Times.

The Home Front Command drills described in report did not include chemical weapons preparation as a major part of the exercises. Two Home Front Command officials also told The New York Times that there had been no widespread reminders to officers or the public about protective measures against such an attack. The Israeli military declined to comment on the reported intelligence.

Netanyahu's office told The Times of Israel: "Israel is following closely every threat from the Iranian terror regime, and is ready to confront them."