The UN Security Council is due to discuss a report on Iran's controversial nuclear programme and may consider sanctions on Tehran. The Iranians say they will continue their nuclear work irrespective of what the UN decides.
Here is what various parties have said about the crisis.
THE UNITED NATIONS
"There's been very close collaboration between... the five permanent members of the council - that's the US, Britain, France, Russia and China... There's going to be a lot of debate, nevertheless, because this is not an easy issue to handle. But I think everybody wants to avoid another Iraq."
UN Deputy Secretary General, Mark Malloch Brown
"I think we need people to lower the rhetoric.... Everybody will benefit from a political settlement of the Iranian issue and it would be a positive implication on an already volatile area..."
IAEA head Mohamed ElBaradei
"Western countries know that they are not capable of inflicting the slightest blow on the Iranian nation because they need the Iranian nation. They will suffer more and they are vulnerable."
Iranian President Mahmoud Ahmadinejad
THE UNITED STATES
"We may face no greater challenge from a single country than from Iran, whose policies are directed at developing a Middle East that would be 180 degrees different from the Middle East that we would like to see develop. This is a country that is determined, it seems, to develop a nuclear weapon in defiance of the international community..."
US Secretary of State Condoleezza Rice
"We'll likely see a presidential statement of the Security Council designed to condemn Iran... But beyond that, if Iran doesn't respond to words and resolutions then we believe the world community should entertain the possibility of sanctions against Iran."
US Undersecretary of State Nicholas Burns
"We are convinced that there is no military solution to this crisis. The same, I believe, is the position of the UK and Germany as publicly stated by their ministers. And I don't think sanctions as a means to solve a crisis have ever achieved their goal.
Russian Foreign Minister Sergei Lavrov
THE UNITED KINGDOM
"It seems to me that the Iranians are being over-confident in some of the assumptions that they're making about the possible consequences of persisting on their current course. I can think of potential consequences that would cause the current regime to rue their failure to understand the need for confidence building - and in particular, the full suspension of all enrichment activities."
UK Ambassador to the IAEA Peter Jenkins
"A crisis of confidence over the nature and aims of the Iranian programme remains. Once again Iran has not taken up the hand extended by the Europeans and their principal partners, including Russia.''
French Foreign Minister Philippe Douste-Blazy
"The actions of the council and the work of the council should be gradual and we would be following a gradual approach... Because we want Iran to go back to suspension, so the actions would be gradual and reversible if Iran goes back to suspension.''
French Ambassador to the UN Jean Marc de la Sabliere
"It is clear that this does not mean the end of diplomacy. On the contrary - the Security Council should add weight to the already existing efforts and decisions of the IAEA. We remain committed to a diplomatic solution.''
German Foreign Minister Frank-Walter Steinmeier
"China appreciates and supports the diplomatic efforts of all parties and call on the international community to exercise patience and restraint in order to give more time to diplomatic efforts.''
Director of the department of Arms Control, Chinese Foreign Ministry, Zhang Yan