The International Atomic Energy Agency has confirmed Iran’s claim that it has begun enriching uranium in an underground bunker in a mountain near the city of Qom. The IAEA said all of the nuclear material in the facility remains under the agency’s surveillance. The United States criticized Iran’s move which comes at a time of heightened tensions between the two nations. On Monday, U.S. State Department spokeswoman Victoria Nuland called on Iran to suspend its enrichment activities.

Victoria Nuland: “But obviously, if they are enriching at Fardo to 20 percent, this is a further escalation of their ongoing violations with regard to their nuclear obligations, including the legally binding U.N. Security Council resolution. So, obviously, we call on Iran, once again, to suspend enrichment activities, cooperate fully with the IAEA and immediately comply with all Security Council and IAEA Board of Governors resolutions.”