A report by US intelligence agencies has contradicted Washington's claims that Iran is actively pursuing a nuclear weapons programme, concluding instead that such work stopped four years ago.
Reaction to the surprise findings has been varied:
Iran's foreign minister, Manouchehr Mottaki:
"It's natural that we welcome it when those countries who in the past have questions and ambiguities about this case ... now amend their views realistically."
The Iranian foreign ministry spokesman, Mohammad Ali Hosseini
"Remarks by Bush and other US administration officials, who have continuously talked about the danger of Iran's nuclear programme, are baseless and unreliable."
Israel's defence minister, Ehud Barak
"It's apparently true that in 2003 Iran stopped pursuing its military nuclear programme for a time. But in our opinion, since then it has apparently continued that programme."
Gordon Brown's official spokesman
"In overall terms, the government believes that the report confirms we were right to be worried about Iran seeking to develop nuclear weapons. It also shows that the sanctions programme and international pressure has had some effect. It also shows the intent is there and the risk of Iran acquiring a nuclear weapon remains a very serious issue."
Harry Reid, the Democrat Senate majority leader
"I hope this administration reads this report carefully and appropriately adjusts its rhetoric and policy vis-a-vis Iran."
The Russian president, Vladimir Putin (speaking to Iran's chief nuclear negotiator)
"We expect that your programmes in the nuclear sphere will be open, transparent and be conducted under control of the authoritative international organisation."
The French foreign ministry's spokesman
"It appears that Iran is not respecting its international obligations. We must keep up the pressure on Iran ... we will continue to work on the introduction of restrictive measures in the framework of the United Nations."