Iran is expanding a nuclear enrichment facility that could provide the country with the means to build nuclear weapons rapidly, according to a report from nuclear experts in The Washington Post.

The expansion of the Fordow Fuel Enrichment Plant, Iran's most heavily fortified nuclear facility, has been verified by inspectors with the International Atomic Energy Agency just a few days after the country formally warned the IAEA about the plans to upgrade the facility.

According to the Post, the expansions could allow Iran to create a stockpile of enriched uranium, which acts as fuel for nuclear weapons, that could be used to create multiple bombs per month. In addition, the facility's location, in the mountains of north-central Iran, makes it naturally fortified against airstrikes and other attacks.

"Iran would gain the capability for a rapid breakout at this deeply buried site, an ability it has not possessed before," David Albright, a physicist and nuclear weapons expert who serves as president of the nonprofit Institute for Science and International Security, told the Post.

"Iran aims to keep expanding its nuclear program in ways that lack any credible peaceful justification," State Department spokesman Matthew Miller told the newspaper in a statement. "These planned actions further undermine Iran's claims to the contrary. If Iran proceeds with these plans, we will respond accordingly."

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