Israeli warplanes struck Gaza’s crowded southern city of Rafah Thursday after US President Joe Biden vowed to stop supplying artillery shells and other weapons to Israel if a full-scale assault goes ahead.

It was the starkest warning yet from the United States, Israel’s main military provider, over the civilian impact of its war against Hamas.

An AFP correspondent and witnesses on Thursday reported Israeli strikes on several parts of Rafah, where the United Nations said 1.4 million people were sheltering.

“The tanks and jets are striking,” Tarek Bahlul said on a deserted Rafah street. “Every minute you hear a rocket and you don’t know where it will land.”

Israel has already defied international objections by sending in tanks and conducting what it called “targeted raids” in the east of Rafah, the city it says is home to Hamas’s last remaining battalions.

The Hamas authorities’ “emergency committee” in Rafah dismissed as “nothing but lies” Israel’s description of its operation as “limited”.

In an interview with CNN on Wednesday, Biden warned he would stop some US weapons supplies to Israel if it carried out its long-threatened ground assault.