DUBAI - United Nations Secretary-General Ban Ki-moon has defended his controversial visit to Iran, saying on Friday that he had used this week's trip to push hard for human rights and transparency from Tehran over its nuclear program.

"I believe in the power of diplomacy and I believe in dialogues and I believe in engagement. This is exactly what I did during my visit to Tehran," Ban told Reuters on a stopover in Dubai before flying back to UN headquarters in New York.

While conceding he had not always been satisfied with the responses of Iranian leaders he spoke to this week, he rejected accusations by the United States and Israel that he had been playing into Tehran's hands by attending an international summit which Iran used to raise its diplomatic profile.

"I think that it should not have been controversial," he said. "As a secretary-general of the United Nations, I have a mandate to engage with all the member states of the United Nations."

Please LIKE our Facebook page - it makes us stronger