Iranian Leaders Defiant Even as Currency Falls Senior Iranian clerics intensified their anti-Western criticism on Friday, calling the near-collapse of the national currency this past week a consequence of an American-led conspiracy to wage an economic war on Iran, and predicting that the pressure would ease. The message, highlighted in the main weekly sermon at Friday Prayer, appeared to be an effort to show a unified and defiant response to the crisis over the currency, the rial, which lost roughly 40 percent of its value against the dollar in a stampede of selling to black-market currency traders by Iranians worried about their country's economic stability. A televised plea on Tuesday by President Mahmoud Ahmadinejad to stop the selling seemed only to heighten the anxiety, and a crackdown by the police against the currency traders and the arrests of suspected speculators on Wednesday escalated into a large protest in Tehran that included merchants in the politically powerful Grand Bazaar. That was the first significant demonstration of anger over the devalued rial, which has injected new uncertainty into the daily lives of Iranians by worsening the already high inflation rate. Many Iranians and outside economic experts have attributed the problems to what they call Mr. Ahmadinejad's mismanagement as well as the accumulating effects of the Western sanctions imposed on Iran over its disputed nuclear energy program. None of the statements about the crisis in the official Iranian news media on Friday offered a hint of any new solutions to the crisis or suggested that the government was willing to compromise on the nuclear program in exchange for reduced sanctions. Instead they exhorted Iranians to show fortitude and uphold the legacy of resilience amid other crises, like the eight-year war with Iraq in the 1980s. "The pressure today imposed on us by the world arrogance is full-fledged economic war," Ayatollah Ahmad Khatami, a top cleric and the Friday Prayer leader, said in his message, carried on official news outlets. This pressure will not last. Our people have been tested, and they will not be worn down. The Fars News Agency quoted a close aide of the supreme leader, Ayatollah Ali Khamenei, as saying that Iran's enemies were mistaken if they believed the sanctions would force Iran to capitulate in the dispute over the nuclear program, which Iran has said is for peaceful purposes. Western powers, however, suspect Iran is developing the ability to make nuclear weapons. "Iran is overcoming the psychological war and conspiracy that the enemy has brought to the currency and gold market, and this war is constantly fluctuating," said the aide, Gholam Ali Haddad Adel. The arrogant powers, in their crude way, think that the nation of Iran is ready to let go of the Islamic Revolution through economic pressure, but we are establishing Iran's economic strength. The message of defiance came as Western officials were contemplating further tightening the sanctions, which have severely limited Iran's ability to sell oil and have expelled Iranian banks from a global network that is crucial in conducting financial transactions. Proponents of stricter economic penalties against Iran have been emboldened by the currency crisis, calling it evidence that the sanctions are working. Mark D. Wallace, chief executive of United Against Nuclear Iran, a New York-based group that has worked to persuade multinational companies to sever business ties with Iran, said that by its calculation Iran's currency had fallen by 80 percent in the past year. In a statement on the group's Web site, he called for an economic blockade on Iran to increase the pressure, saying "the regime must be forced to choose between having a nuclear weapon or a functioning economy."