• Biden says if Israeli troops enter the densely-packed city "we're not going to supply the weapons and artillery shells".
• Israel's ambassador to the UN, Gilad Erdan, calls it a "very disappointing statement".
Heavy shelling is reported in Rafah, in the southern Gaza strip, as US President Joe Biden warns Israel against a major offensive there.
Biden says if Israeli troops enter the densely-packed city "we're not going to supply the weapons and artillery shells".
Israel's ambassador to the UN, Gilad Erdan, calls it a "very disappointing statement".
In Rafah, Scott Anderson, from the UN agency for Palestinian refugees, tells the BBC fighting is moving towards the centre of the city.
Biden's remarks came after the US confirmed it had already delayed a shipment of bombs to Israel, over fears of what could happen in Rafah.
But US Defence Secretary Lloyd Austin said the US would continue "to ensure that Israel has the means to defend itself"