Though Iran has long denied nuclear weapon ambitions, it is "dramatically" accelerating its enrichment of uranium to 60% fissile purity, close to the roughly 90% weapons-grade level, the U.N. nuclear watchdog chief told Reuters in December.

Iran alerted the United Nations on Tuesday to what it described as "reckless and inflammatory statements" by U.S. President Donald Trump threatening the use of force, and warned that "any act of aggression will have severe consequences.

By bnm Tehran bureau As Donald Trump gets settled in the White House, Iran finds itself at a critical juncture, facing both economic pressures and economic challenges. The recent memorandum signed by Trump on February 4,

Iran's President Masoud Pezeshkian accused Donald Trump of hypocrisy and seeking to bring the "Islamic Republic to its knees."