Palestinian ambassador to the UN Riyad Mansour asked the UN on Monday when the world body would say “enough is enough” and lift the blockade on Gaza.
After nearly three days of violence, a ceasefire between Israel and Palestinian militants that took effect late on Sunday was still holding.
Tor Wennesland, the top UN Middle East envoy, on Monday told an emergency meeting of the UN Security Council that “the ceasefire is fragile” and any resumption of hostilities will have “devastating consequences” for Palestinians and Israelis, and make any political progress difficult.
Both sides have reserved the right to respond if the ceasefire is breached.
Mr Wennesland condemned the Palestinian rocket fire while recognising Israel’s security concerns. He said any use of force “must be proportionate", with “all feasible steps” taken to avoid civilian casualties.
Before the meeting, Israeli ambassador to the UN Gilad Erdan called on Monday for the council to place “full accountability” on Islamic Jihad.
“There must be one outcome and one outcome only, to condemn the [militia] for its double war crimes while placing the full accountability … for the murder of innocent Palestinians on the shoulder of the radical terror group,” Mr Erdan said.
“They fire rockets at Israeli civilians while using Gazans as human shields. This is a double war crime."
The weekend's violence was the worst since an 11-day war between Israel and Hamas in May 2021.
Since Friday, Israeli aircraft pummeled targets in Gaza while Islamic Jihad fired hundreds of rockets at Israel. Egypt helped to broker the ceasefire.
The Palestinian Health Ministry said 44 Palestinians were killed. Islamic Jihad said 12 were militants.
Israel said some of the dead were killed by misfired rockets.
News agencies contributed to this report