The Iranian side upped the ante by blaming the United States for Iran's predicament - consideration of its nuclear activities in the U.N. Security Council next week - and threatened retaliation.
''The United States may have the power to cause harm and pain,'' Javad Vaeedi, a senior Iranian nuclear negotiator, told reporters at the end of the meeting. ''But it is also susceptible to harm and pain. So if the United States wants to pursue that path, let the ball roll.''
The threat did not seem to be an off-hand remark. The threat was contained, in almost the same wording and with the same mixed metaphor, in Iran's speech to the 35-nation board of the International Atomic Energy Agency.
In Iran, President Mahmoud Ahmadinejad vowed that those who want to ''violate the rights of the Iranian nation will quickly regret their actions.''
Iran's envoy in Vienna dodged when asked what letting the ball roll meant - perhaps using oil as a weapon or destabilizing the region, for example. Ali Asghar Soltainyeh, Iran's ambassador to the agency, said the matter would be ''carefully'' studied back home.
Wednesday's meeting was Iran's last chance to promise to curb its nuclear activities and avoid judgment by the Security Council.
Consideration of the Iran case by the agency on Wednesday was a diplomatic ritual. No formal resolution was introduced.
Iran's oil minister, Kazem Vaziri-Hamaneh, delivered a very different message in Tehran. He assured an edgy oil market that Iran would continue to export crude even if economic sanctions were imposed.
Noting that sanctions ''could affect'' the oil market and raise prices, ''it will not affect our decision to continue our supply,'' he told reporters on the fringes of a meeting of OPEC oil ministers. ''Oil flow is continuing. The exports will not be stopped.''
The Bush administration's envoy to the nuclear agency, Gregory Schulte, kept up the fierce tone on Wednesday, telling reporters, ''The leadership in Tehran has thus far chosen a course of flagrant threats and phone negotiation.''
