EU and US leaders, as well as Amnesty International, on Friday condemned Iran's threat of crackdown on reformist protesters. US President Barack Obama said he was very concerned by the "tenor and tone" of comment's by Iran's supreme leader Ayatollah Ali Khamenei. In a television interview taped Friday with CBS News' Harry Smith, Obama said that Iran's government should "recognize that the world is watching." He said that "how they approach and deal with people who are, through peaceful means, trying to be heard" will signal "what Iran is and is not." French President Nicolas Sarkozy said he hoped Iran's leaders "don't do anything irreversible" that could further endanger the country's stability. "We support the Iranian people, and today the Iranian people are on the street," he said. German Chancellor Angela Merkel said Ayatollah Ali Khamenei's speech "was rather disappointing," and she reiterated international calls for an official investigation into allegations of vote rigging. Speaking on Sky News, British Prime Minister Gordon Brown said he wants to have a good relationship with Iran in the future. "But that depends on Iran being able to show to the world that its elections have been conducted fairly and that there is no unfair suppression of rights and individuals in that country," Brown said. The 27 EU leaders were unanimous in condemning violence against Iran's opposition protesters, as hundreds of thousands there have rallied in recent days for a recount of presidential ballots. Meanwhile, the House of Representatives voted 405-1 to condemn Iran's crackdown on demonstrators and the government's interference with Internet and cell phone communications. The policy statement expresses support for "all Iranian citizens who embrace the values of freedom, human rights, civil liberties and rule of law" and affirms "the importance of democratic and fair elections." It also condemns "the ongoing violence" by the government and pro-government militias against demonstrators, as well as government "suppression of independent electronic communications through interference with the Internet and cell phones." Rep. Howard Berman, chairman of the House Foreign Affairs Committee and co-sponsor of the resolution, said "it is not for us to decide who should run Iran, much less determine the real winner of the June 12 election. "But we must reaffirm our strong belief that the Iranian people have a fundamental right to express their views about the future of their country freely and without intimidation," added Berman, a Democrat. The resolution was initiated by Republicans as a veiled criticism of Obama, who has been reluctant to speak out against Teheran's handling of disputed elections that left hard-liner President Mahmoud Ahmadinejad in power. Rep. Mike Pence, who co-sponsored the resolution, said he disagrees with the administration that it must not meddle in Iran's affairs. "When Ronald Reagan went before the Brandenburg Gate, he did not say "Mr. (Mikhail) Gorbachev, that wall is none of our business," said Pence, a Republican, of President Reagan's famous exhortation to the Soviet leader to "tear down that wall." Obama told CNBC television this week that "when you've got 100,000 people who are out on the streets peacefully protesting and they're having to be scattered through violence and gun shots, what that tells me is the Iranian people are not convinced of the legitimacy of the election." But, he said, it was "not productive, given the history of US-Iranian relations, to be seen as meddling." Iranians have long blamed the CIA for helping topple the elected government of Mohammad Mosaddeq in 1953 and replacing him with the late Shah Mohammad Reza Pahlavi. Meanwhile Amnesty International has said that Khamenei's speech gives legitimacy to police brutality. In a statement on Friday, the London-based human rights organization said Khamenei's speech "indicates the authorities' readiness to launch violent crackdowns if people continue to protest which may cause a widespread loss of life." "We are extremely disturbed at statements made by Ayatollah Khamenei which seem to give the green light to security forces to violently handle protesters exercising their right to demonstrate and express their views," said Hassiba Hadj Sahraoui, deputy director of Amnesty's Middle East program. "If large numbers of people take to the street in protests in the next couple of days, we fear that they will face arbitrary arrest and excessive use of force, as has happened in recent days, particularly as permission for a demonstration to be held in Teheran on Saturday has been denied." Amnesty said that instead of warning security forces, including the volunteer Basij militia, to act with restraint and in accordance with the law, Khamenei threatened the Iranian people by saying that if they continued to take to the streets, the consequences would lie with them. "For a Head of State to put the onus of security on peaceful demonstrators and not on the security forces is a gross dereliction of duty and a license for abuse," Sahraoui added. Jonny Paul contributed to this report.