Joe Biden ramped up diplomatic efforts to prevent Israel’s anticipated ground assault on Gaza from spiralling into a regional conflagration, telling the country’s prime minister he must follow the rules of war and warning other regional powers not to exploit the situation.

The US president’s push came even as he delivered an emotional address to Jewish community leaders at the White House, where he called Saturday’s Hamas attack on southern Israel “a campaign of pure cruelty against the Jewish people” and vowed to supply Israel with all weaponry it might need. 

Still, Biden’s daylong efforts on Wednesday, which included calls to several leaders in the Middle East, appeared aimed at winning assurances from US allies and foes that they show restraint in the coming days, a sign of growing concerns in Washington that the Israel-Hamas war could destabilise the wider region.