On Tuesday, United Nations Chief Antonio Guterres warned Israel of humanitarian disaster if Gaza's Rafah city invaded.
"A military assault on Rafah would be an unbearable escalation, killing thousands more civilians and forcing hundreds of thousands to flee," the secretary-general told reporters.
Such an operation "would have a devastating impact on Palestinians in Gaza, with serious repercussions on the occupied West Bank and across the wider region," he noted.
"All members of the Security Council, and many other governments, have clearly expressed their opposition to such an operation. I appeal for all those with influence over Israel to do everything in their power to prevent it."
Guterres' remarks came after the Israeli prime minister said an offensive would go forward regardless of a pending hostage deal with Hamas.
Rafah has become a refuge for some 1.5 million Palestinians who have fled Israel's bombardments that have ravaged the territory since the start of the war on October 7, when Hamas launched a deadly and unprecedented attack on Israel.
However, Netanyahu has pledged to destroy Hamas, and he said the Israeli army stopping the war "before achieving all of its goals is out of the question."
"We will enter Rafah and we will eliminate the Hamas battalions there with or without a deal," he told families of hostages still being held in Gaza, his office said.
Guterres called on Israel and the Palestinian Islamist movement Hamas to reach a truce "now," and reiterated his call for Israel to allow more humanitarian aid into Gaza, including through the UN agency for Palestinian refugees, or UNRWA.
"Without that, I fear the war, with all its consequences both in Gaza and across the region, will worsen exponentially," he said.
The secretary-general also expressed his concerns over reports of mass graves discovered at Gaza's two main hospitals, along with allegations those buried there were unlawfully killed.
Follow the latest news on Google News
