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.

The announcement signaled a breakdown in the Israel-Hamas ceasefire deal, the first phase of which expired Saturday with no clear next steps.

Israel ordered an immediate halt to Gaza's electricity supply Sunday in an effort to pressure Hamas into releasing hostages, even as it prepared for fresh talks on the future of its truce with the Palestinian militants.

The latest deaths brought the overall Palestinian death toll from the war to 48,503. More than 110,000 people have been wounded, according to the Gaza Health Ministry.

The head of Gaza’s government media office, accused Israel of deliberately intensifying its attacks on Palestinians over the past 10 days in violation of the ceasefire deal.

Israeli fire has killed eight Palestinians in the Gaza Strip and three more in the occupied West Bank over the past 24 hours, Palestinian officials said Tuesday, even as a fragile ceasefire with Hamas in Gaza has largely held since late January.