Palestinians were warned Monday to evacuate parts of Rafah as Israel dismissed international pressure to spare the densely populated southern Gaza city and instead prepared for an attack certain to worsen an accute humanitarian crisis.

The move also comes despite President Joe Biden repeatedly stating U.S. opposition to an invasion of Rafah, where the population has swelled to an estimated 1.4 million people following Israel’s offensive in Gaza in retaliation for Hamas’ deadly attack on Israel and the taking of hostages on Oct. 7.

The IDF says it will operate against targets in the east of the Gazan city, and residents should move to an "expanded humanitarian zone".