India, June 10 -- The head of the UN-backed nuclear watchdog has raised fresh concerns over Iran's failure to fully cooperate with inspections, warning that this is preventing independent verification of its nuclear activities.

Rafael Grossi, Director-General of the International Atomic Energy Agency (IAEA), said on Monday that Iran's growing stockpile of highly enriched uranium and unresolved questions about its programme remain serious issues.

"Unless and until Iran assists the agency in resolving the outstanding safeguards issues, the Agency will not be in a position to provide assurance that Iran's nuclear programme is exclusively peaceful," he said.

He was addressing IAEA's Board of Governors, which comprises 35 countries - includ...