The United States is still against Israel's plans to carry out an assault on the southern city of Rafah in Gaza, as Prime Minister Benjamin Netanyahu said Tel Aviv set a date for the attack.

President Joe Biden's administration has repeatedly called on Israel to present a plan to protect civilians in Rafah, where some 1.5 million Palestinians have taken shelter from Israel's six-month-old attacks.

"We have made clear to Israel that we think a full-scale military invasion of Rafah would have an enormously harmful effect on those civilians and that it would ultimately hurt Israel's security," State Department spokesman Matthew Miller told reporters on Monday when asked about Netanyahu's remarks.

"It's not just a question of Israel presenting a plan to us. We have made clear to them that we think that there is a better way to achieve what is a legitimate goal, which is to degrade and dismantle and defeat the Hamas battalions that still remain in Rafah," Miller said.

Netanyahu in a video statement Monday did not say when the incursion into Rafah would start but said, "It will happen – there is a date."

Biden last week warned that U.S. support for Israel was on the line unless Israel addresses humanitarian concerns after Israel killed seven aid workers in what its military called a "mistake" besides killing over 32,000 Palestinians, mostly women and children.

Miller praised some initial steps from Israel including an increase in aid trucks entering Gaza and the establishment of a military unit to coordinate with humanitarian workers and avoid conflict.

"While we welcome these initial steps, it's crucial to recognize that much more needs to be done. Many Palestinians in Gaza are at risk of famine, and every single man, woman and child in Gaza is experiencing food insecurity," Miller said.

"We expect Israel to fully implement its commitments quickly, and we will we will be monitoring that implementation," he said.

"Ultimately it is the results that matter and we will be judging them on those results."