NEW : If Iran is enriching uranium to 20 % , `` this is a further escalation of their ongoing violations with regard to their nuclear obligations , including the legally binding U.N. Security Council resolution , '' Nuland said . The U.S. says the enrichment is `` further escalation '' by Iran . The IAEA confirms uranium enrichment has begun at the Fordo plant . In a statement released on Friday, the agency said it had received confirmation that Tehran was continuing to enrich uranium. Iran needs to enrich uranium to 20 % for radioisotopes to treat cancer , Kayhan reports .
NEW : The U.S. says the enrichment is `` further escalation '' by Iran . The IAEA confirms uranium enrichment has begun at the Fordo plant . In a statement released on Friday, the agency said it had received confirmation that Tehran was continuing to enrich uranium. Iran needs to enrich uranium to 20 % for radioisotopes to treat cancer , Kayhan reports .