Hamas militants agreed to resume a cease-fire in the Gaza Strip after a lull in the fighting ended with a barrage of Palestinian rocket and mortar fire that provoked Israel to resume military operations.

Spokesmen for Israeli Prime Minister Benjamin Netanyahu weren’t available for comment on whether Israel would join the United Nations-sponsored truce, which was to take effect at 2 p.m local time. The United Nations’ special envoy to the Middle East, Robert Serry, told Channel 2 TV that he hadn’t heard from the Israeli government on this latest truce call. Air raid sirens continued sounding in Israel into the afternoon.

Sami Abu Zuhri, a spokesman for the militant Hamas group that controls Gaza, dropped earlier conditions for extending the cease-fire that took effect over the weekend, including an Israeli troop pullout. It wasn’t clear why Hamas changed its mind on the truce so soon after rejecting the proposed extension. About 1,150 Palestinians have been killed and more than 160,000 have been displaced in fighting that has also left 45 Israelis and a Thai worker in Israel dead.

“Responding to the U.N. intervention and considering our people’s situation, it was agreed with the Palestinian factions to go for a 24-hour cease-fire that starts 2 p.m. on Sunday,” Abu Zuhri said in a text message.

The offensive, begun July 8 after weeks of rocket fire from Gaza and Israeli air strikes, is the third major military showdown between the sides in less than three years. Previous truce deals have failed to resolve underlying issues including the proliferation of arms in Gaza and Hamas’s demand to end Israel’s economic blockade of the Palestinian territory, initiated in 2006 and joined by Egypt.

Israel says its current campaign is intended to quell the barrage of rockets fired at its towns from Gaza and destroy a network of tunnels militants dug into Israeli territory to carry out attacks. Israel, the U.S. and European Union label Hamas a terrorist group.

The conflict deepened last week after the Israeli military augmented air strikes by sending ground troops into the territory. Israeli financial markets have been mostly unaffected.