The head of the U.N. nuclear watchdog said on Monday Iran's engagement with the IAEA in recent months had helped it "gain a better understanding" of Tehran's disputed nuclear programme.

"I welcome the fact that the practical measures agreed with Iran ... have been implemented by Iran as planned. Iran has engaged with the Agency substantively," Yukiya Amano, director general of the International Atomic Energy Agency, told a meeting of the IAEA's 35-nation board of governors.