Iran resumed uranium enrichment at its underground Fordow plant south of Tehran in a new step back from its commitments under a landmark 2015 nuclear deal, raising alarm from Western powers. The other popular uranium enrichment facility in Iran is at Natanz.
Violation of 2015 nuclear deal
The suspension of uranium enrichment at the long-secret plant was one of the restrictions on its nuclear programme Iran had agreed to in return for the lifting of sanctions.
What is significance of nuclear enrichment?
Uranium enrichment is the sensitive process that produces fuel for nuclear power plants but also, in highly extended form, the fissile material for a warhead.
Iran is now enriching uranium to 4.5%, exceeding the 3.67% limit set by the 2015 deal but less than the 20% level it had previously operated to and far less than the 90% level required for a warhead. Iran has always denied any military dimension to its nuclear programme.
Source: The Hindu
Relevant for GS Prelims & Mains Paper II; IOBR