New Zealand diplomats have joined several other countries in walking out on a speech by Iran's President Mahmoud Ahmadinejad at a major United Nations conference.
The public clash dominated the opening day of a UN review of the Nuclear Non-Proliferation Treaty (NPT), the 40-year-old pact aimed at curbing the spread of nuclear arms.
When Mr Ahmadinejad accused countries that possess nuclear weapons of threatening those that want to develop peaceful nuclear technology, delegates from the United States, Britain, France and many other European countries, as well as New Zealand, got up and walked out.
Confirming New Zealand's particpation in the walkout, Foreign Affairs Minister Murray McCully says Mr Ahmadinejad made extremely offensive comments about other countries, in particular the US.
Labour leader Phil Goff says he wholeheartedly supports New Zealand's joining the walkout.
Iran only non-complying nation - Clinton
Subsequently, the BBC reports, US Secretary of State Hillary Clinton told delegates that Iran had violated its obligations and should be held to account.
"Iran is the only country represented in this hall that has been found by the [International Atomic Energy Agency] board of governors to be currently in non-compliance with its nuclear safeguard obligations," Mrs Clinton said.
"It has defied the UN Security Council and the IAEA and placed the future of the non-proliferation regime in jeopardy, and that is why it is facing increasing isolation and pressure from the international community."
Number of nuclear warheads disclosed
The US Department of Defense later disclosed that it had a total of 5113 nuclear warheads in its arsenal, a closely guarded secret for decades.
Mrs Clinton said the move was aimed at improving transparency and encouraging other nations to comply with the NPT.
"So for those who doubt that the United States will do its part on disarmament, this is our record, these are our commitments and they send a clear unmistakable signal," she told the conference.
Throughout her speech, Mrs Clinton regularly rounded on Iran, accusing Mr Ahmadinejad of offering the same "tired, false and sometimes wild accusations" against the US and others.
'A fire against humanity'
The Iranian president, for his part, criticised nuclear powers for failing to disarm, saying their "production, stockpiling and qualitative improvement of nuclear armaments ... now serves as a justification for the others to develop their own".
"The nuclear bomb is a fire against humanity, rather than a weapon of defence, "Mr Ahmadinejad told the conference. "The possession of nuclear bombs is not a source of pride. Its possession is disgusting and shameful."
The US is currently negotiating with other Security Council members to impose a fourth round of UN economic sanctions against Iran over its uranium enrichment programme, which Tehran insists is entirely peaceful.