The United States warned Israel on Thursday of the risk of “catastrophe” in Rafah, a city in the southern Gaza Strip home to more than a million Palestinians, as the Israeli army prepares a new offensive in the area, AFP reported.

“I have yet to see any evidence of serious planning for such an operation, and to conduct such an operation now, without planning and without thought, in an area where millions of people are hiding would be a disaster,” he said. Spokesman Vedant Patel told reporters about this.

He stressed that the United States “will not support” such a large-scale operation that carries the risk of significant civilian casualties, and recalled that the Rafah crossing is a vital point for the delivery of humanitarian aid to the Gaza Strip.

US Secretary of State Anthony Blinken, who on Thursday wrapped up a trip to the region to promote efforts to end the fighting, made the remarks directly to Israeli Prime Minister Benjamin Netanyahu during his talks in Jerusalem on Wednesday, the spokesman added.

Blinken publicly called on his Israeli ally to consider civilians “first” when preparing for the Rafah operation.

The Israeli military stepped up its strikes on Rafah on Thursday, and Israel’s prime minister said he had ordered preparations for an offensive in the area, raising fears for the fate of the 1.3 million Palestinians stuck there, most of whom have been displaced by clashes in the last months in the north of the Strip.

“I ordered the Israel Defense Forces to prepare an operation in Rafah,” Benjamin Netanyahu explained in a televised speech on Wednesday as the war entered its fifth month.

The United States is urging its Israeli ally to “protect” civilians during its military operations in Gaza, launched in response to Hamas’ unprecedented attack on Israeli territory on October 7.