At least 54 people were killed after Israel launched a barrage of airstrikes at Gaza's southern city of Khan Younis overnight, according to the city's Nasser Hospital.
The night prior, Israel targeted northern and southern Gaza, killing at least 70 people, including almost two dozen children, hospitals reported.
The Israeli military has not commented on the strikes.
The attack coincided with US President Donald Trump's visit to Qatar, part of his larger Middle East tour to discuss regional security and economic opportunities.
Trump started his multiple-day tour in Saudi Arabia on Monday and will conclude in the United Arab Emirates on Thursday. The trip does not include Israel.
Many had hoped the US leader's regional visit could encourage a ceasefire deal or resume humanitarian aid to Gaza. A total Israeli blockade, which entered its third month last week, has raised concerns of a growing humanitarian catastrophe.
UN officials warned that "Israeli plans would 'contravene fundamental humanitarian principles' and deepen the suffering of civilians already enduring severe shortages of food, water, and medical care," according to a statement by the United Nations.
Israel has repeatedly stated the blockade is meant to prevent Hamas from profiting from intercepting the aid flow it controls, in a bid to further weaken the militant group.
Israeli Prime Minister Benjamin Netanyahu vowed to intensify the offensive earlier this week and push ahead with a promised escalation of force.
Netanyahu said Israeli forces were days away from entering Gaza “with great strength to complete the mission (of) destroying Hamas," a statement issued by his office on Tuesday said.
