VIENNA: The board of governors at the UN's nuclear watchdog passed a resolution critical of Iran on Friday, the first of its kind since 2012, as tension mounts over Tehran's nuclear programme.

The resolution was put forward by European states and urges Tehran to provide inspectors from the International Atomic Energy Agency (IAEA) with access to two sites in Iran to clarify whether undeclared nuclear activity took place there in the early 2000s.

It "calls on Iran to fully cooperate with the Agency and satisfy the Agency's requests without any further delay, including by providing prompt access to the locations specified by the Agency".

Iran has been blocking access to the sites for months, prompting a growing diplomatic row.