The second International Nuclear Disarmament Conference kicked off in the Iranian capital of Tehran on Sunday.

Referring to the U.S. use of nuclear weapons in Japan, Iranian Foreign Minister Ali-Akbar Salehi said in the opening ceremony of the conference that the United States is the major violator of Nuclear Non-Proliferation Treaty (NPT).

Salehi added that Israel is the only obstacle to create the Middle East free of nuclear weapons.

Iran's Deputy Foreign Minister Mohammad-Mahdi Akhoundzadeh said in the ceremony that the use of nuclear weapons is a crime against humanity.

Nuclear weapons are the most inhumane weapons in the world, said Akhoundzadeh, adding that the tragic event of Hiroshima and Nagasaki are the apparent examples.

The disarmament conference in Tehran is seeking to voice the public opinion of the world for "a world free from nuclear weapons ", he said.

Tehran's two-day conference brings together delegates from forty different nations across the world, including the United States, ambassadors and representatives from international bodies such as the UN and the International Atomic Energy Agency (IAEA).

Akhoundzadeh told reporters on Saturday that the event comprises three specialized panels which will discuss the doctrines of nuclear powers, will take practical measures to have a world free of weapons of mass destruction and will review regional as well as international disarmament commitments.

The conference will also shed light on Israel's policy of deliberate ambiguity on nuclear weapons, he said, adding that the United States and its allies continue to put pressure on non- nuclear weapons states such as Iran, while ignoring Israel's growing nuclear threat to the Middle East.

Last year, Iran hosted the first Nuclear Disarmament Conference with the theme of "Nuclear Energy for All, Nuclear Weapon for None. "

According to local satellite Press TV, Iran plans to hold the third International Nuclear Disarmament Conference at ministerial level, where the country will once again promote its message that all nations are entitled to peaceful nuclear energy.