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

Iran has warned it will ramp up its nuclear activities after the United Nations nuclear watchdog’s 35-member board of governors adopted a resolution Thursday declaring it in breach of its non-proliferation obligations.

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 tensions rose in the Middle East before further U.