Israel has ordered tens of thousands of Palestinians sheltering in the southern Gazan city of Rafah to evacuate, ahead of a planned offensive.
The eastern third of Rafah has now been evacuated.
Israel's military says so far about 300,000 Gazans have moved towards Al-Mawasi.
Aid agencies estimate Saturday's order affects at least a further 40,000 people, with many fleeing to already crowded camps.
[MAP]More than a million Palestinians have been sheltering in tent camps in Rafah, having escaped fighting elsewhere during the seven-month long war.
Israel is determined to push ahead with its military operation in Rafah, where it says Hamas battallions have been deployed.
The United States, Israel's closest ally, has for weeks urged Israel against entering Rafah.
The White House said on Friday it was watching the developments "with concern".
Joe Biden's administration this week confirmed it had paused a shipment of thousands of bombs over concerns about Israel's invasion of Rafah.
Food running out
Humanitarian organisations say the closure of two key border crossings has meant food and aid is running out in Gaza's south.
Georgios Petropoulos from the United Nations Office for the Coordination of Humanitarian Affairs said workers could not operate in new locations.
"The World Food Program ... will run out of food for distribution in the south by tomorrow," he said.
"That means that people will be left only with the aid that has already been distributed in their shelters, in their homes and on site."
In a video posted on social media platform X from southern Gaza, he added eight out of 12 bakeries the agency was supporting had run out of stock.
ABC/wires
