Russia said the use of a tactical nuclear weapon by the U.S. in Iran would be “catastrophic” after a report that it had not been ruled out as an option for President Donald Trump, who is considering joining Israel’s strikes.

“There is a lot of speculation now,” said Dmitry Peskov, spokesman for Russian President Vladimir Putin, state news agency TASS reported. “Such a development of events would be catastrophic, but there is so much speculation that it is actually impossible to comment on it.”

The question is whether a bunker-buster bomb would be sufficient to destroy Iran’s Fordow uranium enrichment facility, which is built deep into a mountain, or if it would take a tactical nuclear bomb to finish the job.

The Guardian had reported that tactical nuclear weapons were considered more capable of destroying Fordow, citing unnamed defense officials, but that Trump was not presented with or considering them as an option.

Later, Fox News reported that all military options were still on the table for the U.S., citing an unnamed top official, but that the military is very confident bunker-buster bombs could destroy Fordow.

There has been no official comment from the U.S. about whether the use of a tactical nuclear weapon is being considered.

Trump is giving himself two weeks to decide if he should strike Iran, a window of time for Tehran to avert such a fate by abandoning its nuclear program. It denies seeking to build a nuclear bomb, saying the program is for energy purposes.

But Iran has enriched uranium to a level very close to that required for a bomb, and well beyond what is needed for civilian energy. Trump says Iran cannot be allowed to build a nuclear bomb.

This is a developing article. Updates to follow.

U.S. President Donald Trump speaks to reporters about the G7 Summit aboard Air Force One while travelling back to Washington from Canada on June 16, 2025.

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