The American Studies program at the University of Teheran is a bold experiment in a nation locked in bitter confrontation with the United States - at a school where chants of "Death to America!" still punctuate Friday prayers. The two-year-old master's degree program tries to teach American government, culture and society to some of Iran's top students, with minimum political judgment. It even planned to send some of its first graduates to the US this summer for nine months of thesis research and teaching Persian to American students. But the trip - a rare academic outreach - has been called off amid accusations of espionage, the latest victim of the increasingly poisoned relationship between the US and Iran. The controversy grew hot enough that Iran's Foreign Ministry weighed in, with spokesman Mohammad Ali Hosseini charging at a news conference that "Americans, under cover of academic cooperation, are pursuing their own goals" - an apparent reference to regime change. "I'm really sorry that this trip is canceled," one of the students said on condition of anonymity because he feared the reaction from hard-liners. "This was really an opportunity that I could learn a lot and bring it back to Iran." The overseas study plan began to fall apart when its sponsor - a US nonprofit organization partially funded by the State Department - told three students that no American university had accepted them, said English professor Mohammad Marandi, the Virginia-born co-founder of what he described as the Islamic republic's first and only American Studies program. Marandi described the three as highly qualified and said many believed they were rebuffed because they are vocal critics of American foreign policy. The trip's sponsor, the New York-based Institute of International Education, refused to comment on any aspect of the Iranian students' trip, e-mailing a generic statement on the program and not responding to further questions. Other institute officials also did not respond to repeated requests for comment. Meanwhile, the three students' supporters became irate, suggesting the overseas trip was part of a broader US attempt to undermine the Iranian system. A conservative Iranian political Web site accused the US of "intending to use university students as its political tools." Teheran University officials charged that the program had become politicized and said that none of the 23 accepted students _ from the American Studies and foreign language program _ could go, Marandi said. The rejected students "want to understand America, and they perhaps would like a platform there to criticize the American government," he said. "If the Americans really want to improve relations between the two sides, they have to be more open." Negotiations are continuing, Marandi said, but the trip is extremely unlikely to be revived. "It's off," he said. Espionage accusations are part of an increasingly common refrain - that the Bush administration is using academics to undermine the Islamic system by spreading secular, liberal values. Four Iranian-Americans - three academics and a journalist - have been arrested on charges they were part of a US plot to foment a "velvet revolution" against the Iranian system. Despite the soured politics, the program had appeared to be thriving. The Institute for North American and European Studies was founded by Saied Ameli, a communications professor who lived in California as a teenager and studied mechanical engineering at the University of Sacramento. He returned to Iran after the overthrow of the US-backed shah, became a highly respected cleric and earned a Ph.D. in sociology. Other classes are taught by a former Iranian ambassador to Canada, and by Marandi, a US citizen who moved back to post-revolution Iran with his parents and volunteered at age 16 to fight in the Iran-Iraq war. The institute is tucked behind a high wall at the end of a blind alley away from Teheran University's main campus. Inside the single-classroom building, students calmly debate topics ranging from housing starts and interest rates to the effect of the Sept. 11 attacks on US foreign policy. Many students say their ultimate goal is to ease relations and promote knowledge of the United States. Others said they were studying the enemy to better understand it. Attitudes toward the US range from acknowledgment of its cultural impact on Iranian society to denunciation of its support for Israel. At one lecture, according to the program's Web site, guest professor Dr. Amir Hossein Ferdows described Jews as "a real danger to the world" who "killed Christ" - a view that Marandi says does not reflect the institute's teaching. "America is a major issue in Iran for everybody," student Mahshid Mayar said. "People know about it, they are living it, because it is influencing their lives, influencing their future."