Abutting the Egyptian border, Rafah's population has been swollen by more than a million Palestinians who fled the half-year-old Israeli offensive through the rest of Gaza.

Their fate worries Western powers as well as Cairo, which has ruled out any influx of refugees into the Egyptian Sinai.

After weeks of talks with the United States about civilian safeguards, Israel's Defence Ministry has bought 40,000 tents, each with the capacity for 10 to 12 people, for Palestinians relocated from Rafah, Israeli government sources said.

Video circulated online appeared to show rows of square white tents going up in Khan Younis, a city some 5 km (3 miles) from Rafah.

Reuters could not verify this, but received images from satellite company Maxar showing multiple tent camps on Khan Younis land that had been vacant on April 7.

Israel's Defence Ministry declined all comment.

The government sources said Prime Minister Benjamin Netanyahu's war cabinet planned to meet in the coming two weeks to authorise civilian evacuations - expected to take around a month - as the first stage of the Rafah sweep.

Netanyahu's office had no immediate comment.

While not discussing specific battle plans, the Israeli military has increasingly signalled readiness to move on Rafah.

"Hamas was hit hard in the northern sector. It was also hit hard in the centre of the Strip. And soon it will be hit hard in Rafah, too," Brigadier-General Itzik Cohen, commander of the 162nd Division operating in Gaza, told Kan public TV on Tuesday.

"Hamas should know that when the IDF (Israel Defence Forces) goes into Rafah, it would do best to raise its hands in surrender. Rafah will not be the Rafah of today... There won't be munitions there. And there won't be hostages there."

On Wednesday, the military said it had mobilized two reservist brigades for missions in Gaza.

Israel says Rafah is home to four intact Hamas combat battalions which have been reinforced by thousands of the Islamist militant group's retreating fighters. Victory in the Gaza war, launched after Hamas' cross-border killing and kidnapping spree on Oct. 7, is impossible without taking Rafah, crushing Hamas and recovering any hostages there, Israel says.

Hamas does not comment on its deployments.

In a speech on Tuesday marking the 200th day of the war, Hamas armed wing spokesperson Abu Ubaida said Israel has achieved only "humiliation and defeat" in a campaign that Gaza medical officials say has killed more than 34,000 Palestinians.

Hamas killed 1,200 people and abducted 253 on Oct 7, according to Israeli tallies. Of those hostages, 129 remain in Gaza, Israeli officials say. More than 260 Israeli troops have been killed in ground fighting since Oct 20, the military says.

For the displaced in Rafah, another evacuation appears grim.

Aya, 30, who has been living temporarily in the city with her family in a school, said she is considering leaving. But she is worried it would be too dangerous. She said that some families recently moved to a refugee camp in coastal Al-Mawasi, but their tents caught fire when tank shells landed nearby.

"I have to make a decision whether to leave Rafah because my mother and I are afraid an invasion could happen suddenly and we won't get time to escape," she said. "Where do we go?"

H. A. Hellyer, a senior associate fellow in international security studies at the Royal United Services Institute, said he expected the assault on Rafah "sooner rather than later" because Netanyahu is under pressure to meet his stated objectives of rescuing the hostages and killing all the Hamas leaders.

"The invasion of Rafah is unavoidable because of the way he has framed all of this," he said. But it will not be possible for everyone to leave the city, so "if he sends the military into Rafah, there are going to be a lot of casualties".

Egypt said it warned Israel against moving on Rafah. Such a move, Egypt's State Information Service said, "would lead to massive human massacres, losses (and) widespread destruction".