A crisis over new Israeli security measures at a Jerusalem holy site must be resolved by Friday to avoid an escalation of violence, the UN envoy to the Middle East said Monday.

"It is extremely important that a solution to the current crisis be found by Friday this week," said Nickolay Mladenov after briefing the UN Security Council.

"The dangers on the ground will escalate if we go through another cycle of Friday prayer without a resolution to this current crisis," he warned.