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

The United Nations nuclear watchdog’s Board of Governors has approved a resolution declaring Iran is not complying with its commitment to international nuclear safeguards, diplomatic sources told Al Jazeera.

The UN nuclear watchdog's 35-nation board of governors passed a resolution on Thursday formally declaring Iran in breach of its non-proliferation obligations for the first time in almost 20 years, with Tehran responding that it would open a new uranium enrichment site.