WASHINGTON - June 19 - This morning's speech by Iran's Supreme Leader, Ayatollah Khamenei, indicates the authorities' readiness to launch violent crackdowns if people continue to protest which may cause a widespread loss of life, Amnesty International said today.

"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 the Middle East and North Africa 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 Tehran on Saturday, June 20, has been denied."

In a televised address to the nation during Friday prayers in Tehran, Ayatollah Khamenei called for an end to street protests against the outcome of the election. Instead of warning security forces, including the volunteer Basij militia, to act with restraint and in accordance with the law, he said that if people 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," said Hassiba Hadj Sahraoui.

Peaceful assembly is expressly permitted under the International Covenant on Civil and Political Rights to which Iran is a state party. Law enforcement officials must use force only when strictly necessary and to the extent required for the performance of their duty. They must not use firearms unless strictly unavoidable and in order to protect life. Law enforcement personnel must exercise restraint, minimize damage or injury and respect and preserve human life.