A senior US arms control official on Wednesday refused to comment when asked during a congressional hearing if Israel has nuclear weapons, maintaining the US government’s ambiguity over Israel’s undeclared nuclear arsenal.
“I can’t comment on that specific question. I’d have to refer you to the Israelis on that,” Thomas DiNanno, the US undersecretary of state for arms control and international security, told Rep. Joaquin Castro (D-TX) when asked about Israel’s nuclear capabilities.
We are four weeks into a war where both sides have targeted each other's nuclear facilities.
— Joaquin Castro (@JoaquinCastrotx) March 25, 2026
We risk nuclear disaster. Yet the main Trump official on arms control refused to answer my question on Israel's nuclear capabilities and told me to ask the Israeli government. pic.twitter.com/Sxnru3EIrl
Castro asked why DiNanno wouldn’t answer whether or not Israel has nuclear weapons, but DiNanno continued to say he wouldn’t comment. “I don’t understand why this issue is so taboo when it’s a basic question, and we’re in a war alongside Israel against Iran. We’re dealing with the potential for nuclear fallout, and you won’t answer this basic question,” Castro said.
Every US presidential administration since President Nixon has maintained an understanding with Israel under which the US and Israel do not acknowledge Israel’s nuclear weapons program, and the US doesn’t pressure Israel to sign the Non-Proliferation Treaty. The ambiguity has allowed the US presidents to provide military assistance without worrying about the 1976 Symington Amendment, a foreign assistance law that prohibits aid to countries that traffic in or receive nuclear enrichment equipment or technology outside of international safeguards.
Israel’s nuclear arsenal, which is estimated to be somewhere between 70 and 400 nuclear warheads, is almost always missing from the conversation in US media coverage and political discussions surrounding Iran’s nuclear program, which has never been used to develop weapons. Unlike Israel, Iran is a signatory of the NPT, and Ayatollah Ali Khamenei, the Iranian supreme leader killed by an Israeli strike on February 28, had maintained a Fatwa banning the development of nuclear weapons.
Iran recently targeted the Israeli city of Dimona, which is near the Shimon Peres Negev Nuclear Research Center, a facility where Israel first developed nuclear weapons in the 1960s and is believed to still be a crucial part of Israel’s undeclared nuclear weapons program. Last year, The Associated Press reported that satellite images showed construction work on a major new facility at the Dimona nuclear site, and seven experts who examined the images all told the AP that they believed the construction was related to Israel’s nuclear weapons program.
