Iran opened on Saturday an international conference on nuclear disarmament and non-proliferation in Tehran.

Iran's Foreign Minister Manouchehr Mottaki said at the opening session of the conference that holding this conference in Tehran shows that the issue of global disarmament of mass destruction weapons, especially the nuclear disarmament, is of great importance for the world.

The conference will focus on three major topics of disarmament challenges, international obligations for disarmament and non- proliferation and practical steps for the materialization of disarmament.

In a message to the conference, Iran's supreme leader Ayatollah Ali Khamenei said that "The use or even the threats to use such (nuclear) weapons is an obvious violation of humanitarian principles and is an evidence for war crime."

"We believe that, besides the nuclear weapons, other kinds of weapons of mass destruction such as chemical and biological weapons are also against humanity," said Khamenei.

"Iran is ready to harness all its capacities to confront (the proliferation and use of) such weapons," he said, adding "We consider the use of such weapons as Haram (religiously prohibited). "

The conference dubbed "Nuclear Energy for all, Nuclear Weapons for None" will last for two days.