The talks, first reported by Reuters, are expected to span topics including reducing Palestinian civilian casualties, securing a temporary ceasefire, the release of hostages held in Gaza and increasing aid to the territory, a White House official said.

"The Vice President will express her concern over the safety of the as many as 1.5 million people in Rafah," the official said, adding that Israel also had a "right to defend itself in the face of continued Hamas terrorist threats."

A statement from Gantz confirmed that he would meet with Harris, as well as with U.S. National Security Adviser Jake Sullivan and Republican and Democratic members of U.S. Congress.

"Minister Gantz personally updated the prime minister on his own initiative on Friday of his intention to travel, in order to coordinate the messages to be transmitted in the meetings," the statement said.

Gantz, Israel's former military chief and defense minister, is Prime Minister Benjamin Netanyahu's main political rival in opinion polls. His trip to Washington risks upsetting Netanyahu, who has been subject to criticism by U.S. President Joe Biden.

In December, Biden said that Israel was losing support over its "indiscriminate" bombing of Gaza and that Netanyahu should change, exposing a rift in relations with the Israeli prime minister.

Harris and Gantz will also discuss planning for after the war ends to revitalize Gaza under the Palestinian Authority, the White House official said.

The U.S. military on Saturday carried out its first airdrop of humanitarian aid into Gaza and aid agencies warned of a growing humanitarian disaster in the Palestinian enclave as Israel pressed on with its offensive.

Plans for the U.S. airdrop were announced by Biden on Friday, a day after the deaths of Palestinians queuing for aid drew renewed attention to the humanitarian catastrophe.

Health authorities in Gaza said 118 people were killed in Thursday's incident, attributing the deaths to Israeli fire and calling it a massacre. Israel disputed those figures and said most victims were trampled or run over.

Israel launched the offensive in response to the Oct. 7 attack by the Palestinian militant group, in which 1,200 people were killed in Israel and another 253 abducted, according to Israeli tallies.

International pressure for a ceasefire has grown, with more than 30,000 Palestinians killed in Israel's Gaza offensive, according to Gaza health authorities, and the U.N. warning that a quarter of the population is one step away from famine.

The United States and other countries expect aid would be boosted by a temporary ceasefire, which Biden said on Friday he hoped would happen by the time of the Muslim fasting month of Ramadan, which starts on March 10.

Gaza truce talks are due to resume in Cairo on Sunday, two Egyptian security sources said on Saturday, though an Israeli news outlet reported Israel would not send a delegation until it received a full list of Israeli hostages who are still alive.

The Egyptian sources said Israeli and Hamas delegations were expected to arrive in Cairo on Sunday.