The head of the International Atomic Energy Agency has raised new concerns about Iran's and North Korea's nuclear programs in his annual report to the United Nations General Assembly.

Yukio Amano, IAEA's director general, reaffirmed Tuesday his agency's recent reports that Iran “is not providing the necessary cooperation to his agency” to prove that all nuclear material in Iran is for peaceful activities.

The United States and many other nations accuse Iran of pursuing a nuclear bomb, which Teheran government denies.

Amano also said that North Korea's nuclear program “remains a matter of serious concern.” He noted that his agency has not been able to implement any safeguard measures in North Korea since April 2009. In May of that year Pyongyang conducted his second nuclear test, calling it successful.

Amano said that last year's reports about the construction of a new uranium enrichment facility and alight water reactor in North Korea also are deeply troubling.

IAEA's chief called on both countries to implement all the relevant international obligations to ease global concerns about their nuclear activities.

The UN Security Council has ordered several rounds of sanctions against Iran over its uranium enrichment. North Korea also is under sanctions.

In 2009, Pyongyang abandoned six-nation talks on its nuclear disarmament in exchange for aid, but has recently insisted that it wants to return to the negotiating table.