Israeli border police are seen inside the Al-Aqsa Mosque compound after firing teargas or a smoke grenade in Jerusalem’s Old City on Sep. 13.

The U.N.’s Mideast envoy warned on Tuesday that clashes between Israelis and Palestinians in and around Jerusalem’s holy sites have the potential to ignite violence well beyond the walls of its old city, pointing to “a vicious tide of terror and extremism” in the region.

Nikolay Mladenov urged all parties to refrain from “provocative actions and rhetoric” and called on political, community and religious leaders to ensure that visitors and worshippers “demonstrate restraint and respect for the sanctity of the area.”

He told the U.N. Security Council by video link Tuesday that the clashes followed “sweeping restrictions” that Israel imposed on entry to Jerusalem’s most sensitive holy site, the Al-Aqsa mosque compound, on Aug. 26. Since then, he said, Israel has banned members of Muslim and Jewish groups considered to be extremist.

“These latest incidents have echoed widely and have been condemned across the Muslim world and beyond,” Mladenov said.

“It is imperative that the historic status quo is preserved” in line with agreements between Israel and Jordan’s King Abdullah II, who is custodian of the Muslim holy sites in Jerusalem, he said.

Mladenov said that Israel’s Prime Minister Benjamin Netanyahu has said his government “will use all means to maintain the status quo and law and order on the compound.”

He also noted “bold, concrete actions” are needed on the ground, in the region and internationally to reach a two-state solution.

The Quartet of Mideast mediators — the U.N., U.S., European Union and Russia — and key Arab nations will meet on September 30, according to Mladenov, on the sidelines of the General Assembly’s annual ministerial meeting to discuss how to link regional and international efforts to create conditions for a return to “meaningful negotiations.”