A cease-fire between Israeli forces and Palestinian militants held overnight into Monday after nearly three days of violence that killed dozens of Palestinians.
An Egyptian-brokered ceasefire came into force at 8.30pm GMT and held despite isolated weapons fire from both sides in the minutes before.
At least 43 Palestinians were killed over three days, including 15 children and four women, and 311 were injured, the Palestinian Health Ministry said.
Israel has accused Palestinian Islamic Jihad of causing some of the deaths with misfired rockets. The rockets threatened much of southern Israel and sent residents in cities including Tel Aviv and Ashkelon to shelters.
Israeli aircraft had struck targets in Gaza since Friday, while the Iran-backed militant group fired hundreds of rockets at Israel in response.
Hamas, the governing Islamist group in Gaza, had stayed out of the conflict.
In a statement, US President Joe Biden called for an investigation into civilian casualties, whether by “Israeli strikes against Islamic Jihad positions or the dozens of Islamic Jihad rockets that reportedly fell inside Gaza.”
He said: “We also call on all parties to fully implement the ceasefire, and to ensure fuel and humanitarian supplies are flowing into Gaza as the fighting subsides.”
Israel had launched what it called pre-emptive strikes on Friday against what it said would be an Islamic Jihad attack meant to avenge the arrest of a leader of the group, Bassam al-Saadi, in the occupied West Bank.
In response, Islamic Jihad fired hundreds of rockets at Israel. On Sunday the group extended its missile attacks to fire toward Jerusalem in what it described as retaliation for the overnight killing of its southern Gaza commander by Israel.
Israel said its Iron Dome interceptor shot down the rockets just west of the city.
The military said others had fallen short, causing several Gaza fatalities, while Hamas said all the Palestinian deaths were caused by the Israeli strikes.
The UN Security Council has scheduled an emergency meeting for Monday on the violence.
"We underscore our commitment to do all we can towards ending the ongoing escalation, ensuring the safety and security of the civilian population, and following-up on the Palestinian prisoners file," said UN Special Coordinator for the Middle East Peace Process, Tor Wennesland, in a statement.