The major step is the culmination of several festering stand-offs between the International Atomic Energy Agency and Iran.

Western nations are planning to table a resolution at an IAEA meeting that will find Iran in non-compliance with its so-called safeguards obligations for the first time in 20 years, a senior western diplomat said.

The U.N. nuclear watchdog's board of governors declared Iran in breach of its non-proliferation obligations on Thursday and Tehran announced counter-measures, as an Iranian official said a "friendly country" had warned it of a potential Israeli attack.

The IAEA held a board session Wednesday on Iran's nuclear program, during which Britain, France, and Germany warned Iran that its escalating nuclear activities—such as 60 percent enrichment of uranium and expansion of centrifuge and stockpile limits—undermine the JCPOA, a 2015 deal with Iran, but did not call for immediate punitive steps.

Iran announced Thursday it will launch a new uranium enrichment facility after the United Nations nuclear watchdog determined the country was not in compliance with its nuclear obligations. The

Board of Governors has passed resolution formally declaring Iran noncompliant with its nonproliferation obligations for the first time since 2005, a move Tehran immediately condemned.