"Political leaders do not have the luxury of time and must rise to the moment," Jeanine Hennis-Plasschaert, the UN envoy to Iraq, said in a video presentation to the UN Security Council.

The envoy noted that more than 400 people have been killed and more than 19,000 injured in two months of unrest in Iraq that has pitted protesters demanding sweeping reform against security forces.

Last week, prime minister Adel Abdel Mahdi resigned in the face of a fresh wave of protests, and Iraqi leaders were meeting in Baghdad Tuesday to search for a way out of the crisis.

Hennis-Plasschaert warned that attempts to buy time with "band-aid solutions and coercive measures ... will only further fuel public anger and distrust."

"The vast majority of protesters are evidently peaceful," Hennis-Plasschaert said. "Any and all forms of violence are intolerable, and must not distract from the rightful demands for reform."

However, she said that despite a review of the rules of engagement to minimize the use of lethal force, "the harsh reality is that the use of live fire has not been abandoned."

"Non lethal devices -- such as tear gas canisters -- continue to be used improperly causing horrific injuries or death, ... unlawful arrests and detentions continue to take place -- as do abductions, threats and intimidation," she said.