"Any notion of threat of attack, or attack, by the Americans is purely absurd," said Sirus Naseri, a senior member of Iran's delegation to the UN nuclear watchdog.
"The US is simply too vulnerable with its overstretched presence in the region to engage in such silly threats or attacks," he said on Wednesday, referring to Washington's military presence in Iraq and Afghanistan.
Asked if he thought the United States might be bluffing by
refusing to rule out the military option, Naseri said Washington
should be open about any possible plans to destroy Iran's atomic sites with military force.
"If there is any truth in this (that attacking Iran is a
real option) I think what the Iranians would say is put it on
the table," Naseri said in an interview.
Earlier, US President George Bush and German Chancellor Gerhard Schroeder put aside their dispute over Iraq and united in warning Iran against developing a nuclear weapon.
Bush (L) and Shroeder warned
Iran against developing N-weapon
Bush, who is on the second leg of a visit aimed at repairing transatlantic ties hurt by the Iraqi war, said in the German city of Maines: "It's vital that the Iranians hear the world speak with one voice that they shouldn't have a nuclear weapon.
"We absolutely agree that Iran must say no to any kind of nuclear weapons, full stop," Schroeder said through an interpreter at a joint press conference following closed-door meetings with his guest.
At the same time, Bush also sought to soothe European worries that he plans to use military force against Iran, saying that "all options are on the table", but stressing that "diplomacy is just beginning" and that "Iran is not Iraq".
Meanwhile, Iranian Foreign Minister Kamal Kharazi said on Wednesday that Tehran was determined to press ahead with uranium enrichment.
"We are determined to continue enrichment and others cannot stop us," he said.
Iran has vehemently denied it is pursuing a nuclear weapons programme and has said its uranium enrichment programme is to meet growing energy needs.
Kharazi also said: "They cannot do anything with bullying, threats and pressure."
Foreign Minister Kamal Kharazi
says bullying will not help
Ismail Baha al-Din, a journalist speaking to Aljazeera from New York, said: "The Americans seem to have given the Europeans some breathing space regarding Iran.
"The US seems to be giving them time to deal with Iran without increasing political or military pressure at this stage."
While Bush backs British, French and German diplomatic overtures to Iran, he is increasingly impatient with Tehran's response, and he has repeatedly refused to rule out the use of force.
With the US and Europe eager to move beyond Iraq, Schroeder said in a German newspaper: "There are occasional differences over issues which are completely normal in a close partnership.
Allies and partners
"We are allies and partners in the fight against terrorism, against the proliferation of weapons of mass destruction, against poverty and epidemics such as Aids," Schroeder wrote in his article for the Bild newspaper.
Baha al-Din also said the US sought a significant European presence in Iraq to ease its burden. It sought a contribution of troops from Nato and the EU to be deployed in Iraq for training security forces.
Germany provides the bulk of
Nato's troops in Afghanistan
Bush, however, noted that Germany had signed on to help Iraq through debt relief and other measures and took pains to downplay Berlin's refusal to send troops or train Iraqi security forces inside Iraq.
"I fully understand the limitations" Germany faces, he said, adding that Berlin's contributions were "not limited, they're important".
New York-based journalist Baha al-Din told Aljazeera that during Bush's second-term, "the US is more aware of Europe's political clout especially in being its only possible rival".
"Bush also sees a united Europe as a good ally due to its economic and regional influence," he added.
Bush and Schroeder, who were barely on speaking terms after the chancellor opposed the March 2003 invasion of Iraq, met on Wednesday together with US and German troops that have served in Afghanistan.
"The US is more aware of Europe's political clout especially in being its only possible rival"
Ismail Baha al-Din,
New York-based journalist
Germany provides the bulk of troops within the Nato-run, 8300-strong International Security Assistance Force (ISAF), which was deployed to provide security after the US invaded Afghanistan.
But Bush's visit was not all pleasant.
Aljazeera's correspondent in Germany, Aktham Sulaiman, said demonstrators on Tuesday had taken to the streets in Mainz.
Banners stating "Not Welcome, Mr Bush" await the US president.
He added that protesters in Berlin and Frankfurt were prevented from demonstrating by strict security measures.
Bush was to address US soldiers at an army base in Mainz.