The United States anchored a temporary floating pier to a beach in Gaza on Thursday to boost aid deliveries, but it was still unclear how it would be distributed given the challenges that have beset the United Nations and relief groups for months.
The United Nations stressed that delivering aid by land was the "most viable, effective and efficient" method.
"To stave off the horrors of famine, we must use the fastest and most obvious route to reach the people of Gaza – and for that, we need access by land now," deputy UN spokesperson Farhan Haq said.
"We don't want ships... we want safety," said displaced Gazan Hassan Abu Al-Kass, speaking in the central Gaza Strip.
The United States State Department said the humanitarian situation in Gaza continued to deteriorate and urged Israel to allow sustained access for aid via the southern and northern parts of the enclave.
Israel's military says its operation in Rafah is meant to kill Hamas fighters and dismantle infrastructure used by the group, which governs the blockaded Palestinian territory. Israel accuses Hamas of diverting aid, something it denies.
Egyptian sources said Cairo, which fears a mass exodus from Gaza to Egypt, had rejected an Israeli request to coordinate on the reopening of the Rafah border crossing, which Israel seized on May 7, and keep it beyond Palestinian control.
Ceasefire and hostage release talks are deadlocked over how to end the war.
Hamas chief Ismail Haniyeh said his group, which has run Gaza since 2007, should continue to have a role while the Palestinian Authority, which Western leaders want to oversee Gaza, said it did not have enough funds to fulfil its current limited governing role in the Israeli-occupied West Bank.
Israel declared major operations over in northern Gaza months ago while pledging to return to prevent Hamas regrouping.
On Thursday, around a week after they moved back in, Israeli tanks were heavily bombarding the main market in the heart of Jabalia, a decades-old refugee camp, and several stores there caught fire, residents and Hamas media outlets said.