Iran is escalating its fight with the United Nations nuclear watchdog by accusing its inspectors of slander and presenting sloppy evidence, according to a legal brief compiled by the Islamic Republic and circulated among diplomats days before a key meeting in Vienna.

An outline by the Trump administration would allow Iran to continue enriching uranium at low levels while a broader arrangement is worked out that would block the country’s path to a nuclear weapon.

Newsweek has reached out to the U.S. State Department for comment. Why It Matters. The remarks are the first time Tehran has commented on the content of the recent U.S. proposal,

Iran’s supreme leader, Ayatollah Ali Khamenei, said on Wednesday that abandoning uranium enrichment was “100 percent” against Tehran’s interests, effectively rejecting a key U.S. demand in weeks of tense negotiations over Iran’s nuclear program.

The outline of the U.S. offer to Iran in their high-stakes negotiations over Tehran's nuclear program is starting to become clearer — but whether any deal is on the horizon remains as cloudy as ever.

By Francois Murphy and John Irish VIENNA (Reuters) -U.N. inspectors monitoring Iran's Fordow nuclear site confronted a major gap in their knowledge last year as they watched trucks carrying advanced uranium-enriching centrifuges roll into the facility dug into a mountain south of Tehran.