A top UN official on Tuesday pushed world powers and Iran to urgently work to restore a 2015 deal that lifted sanctions on Tehran in return for restrictions on its nuclear program. The UN nuclear watchdog IAEA last week reported that Iran has increased its uranium enrichment to up to 60% purity at Fordow, which is close to the 90% needed for nuclear weapons.

The US-led West saw Iran’s move, which is cited in IAEA report, as a serious escalation.

Iran, which has repeatedly claimed its commitment to cooperate with IAEA rejected the "unfounded" accusations in front of the JCPOA deal members.