An Israeli air strike killed four Palestinians in Gaza, the territory's civil emergency service said, as Arab mediators and the United States tried to hammer out differences between Hamas and Israel over a January 19 ceasefire agreement.

Israel launched a large-scale military operation centered on Jenin shortly after reaching a fragile ceasefire with Hamas in the Gaza Strip in January. Troops have destroyed homes and infrastructure, and tens of thousands of Palestinians have fled their homes across the northern West Bank.

While fighting has not resumed since the March 1 ceasefire expiration, Israel has cut off humanitarian aid to Gaza to press Hamas.

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The two sides are supposed to negotiate a second phase of the cease-fire agreement that would end the war, but they remain far apart on how to move forward.