The UN security council has voted to demand an immediate ceasefire in Gaza for the first time since the start of the Israel-Hamas war, after the US dropped a threat to veto, bringing Israel to near total isolation on the world stage.

The US abstained and the 14 other council members all voted in favour of the security council ceasefire resolution, put forward by the 10 elected council members who voiced their frustration with more than five months of deadlock between the major powers.

The text demanded “an immediate ceasefire for the month of Ramadan leading to a lasting sustainable ceasefire”. It also demanded the release of hostages but did not make a truce dependent on them being freed, as Washington had previously demanded.

The vote signaled a significant break between the Biden administration and the Israeli government, and represented a long-delayed show of international unity on Gaza after more than 32,000 Gazans have been reported dead, thousands more are missing, and UN agencies are warning that a major famine is imminent.

The Palestinian envoy to the UN, Riyad Mansour, called it a belated “vote for humanity to prevail”.

“This must be a turning point. This must lead to saving lives on the ground,” Mansour told the council. “Apologies to those who the world has failed, to those that could have been saved but were not.”

Israel’s prime minister, Benjamin Netanyahu, alleged the US had “abandoned its policy in the UN” with Monday’s abstention, giving hope to Hamas of a truce without giving up its hostages, and therefore “harming both the war effort and the effort to release the hostages”.

The isolation of the Israeli government was underlined even further on Monday, when the Israel Hayom newspaper published an interview with Donald Trump, a close political ally of Netanyahu, who said: “You have to finish up your war.

“Israel has to be very careful, because you’re losing a lot of the world, you’re losing a lot of support,” Trump said.

Hamas welcomed the resolution and said it stood ready for an immediate exchange of prisoners with Israel, raising hopes of a breakthrough in negotiations under way in Doha, where intelligence chiefs and other officials from the US, Egypt and Qatar are seeking to broker a deal that would involve the release of at least 40 of the estimated 130 hostages held by Hamas for several hundred Palestinian detainees and prisoners, and a truce that would last an initial six weeks.

After the vote, Netanyahu’s office cancelled a visit to Washington by two of his ministers, intended to discuss a planned Israeli offensive on the southernmost Gazan city of Rafah, which the US opposes. The White House said it was “very disappointed” by the decision. However, a previously arranged visit by the Israeli defence minister, Yoav Gallant, went ahead.

In Washington, Gallant insisted Israel would go on fighting until the hostages were released.

“We have no moral right to stop the war while there are still hostages held in Gaza,” Gallant said before his first meeting, with the US national security adviser, Jake Sullivan. “The lack of a decisive victory in Gaza may bring us closer to a war in the north.”

The “war in the north” appeared to a reference to a looming conflict with Hezbollah in Lebanon, and a suggestion that Hezbollah would see the lack of victory in Gaza as a sign of weakness.

The US abstention followed three vetoes of earlier ceasefire resolutions, in October, December and February. It marks the significant widening of a rift with the Netanyahu government, reflecting mounting frustration in Washington at the prime minister’s defiant insistence Israeli forces will go ahead with the Rafah attack, and at persistent Israeli hindrance of humanitarian aid deliveries.

Minutes before the vote on Monday morning, the US asked for an amendment adding a condemnation of Hamas for its attack on Israel on 7 October, leading to urgent huddles of diplomats on the chamber floor, but dropped that demand when it became clear the amendment would be resisted. The US did however prevail over the weekend in replacing the word “permanent” with “lasting” in describing the ceasefire that was the ultimate goal of the resolution.

Linda Thomas-Greenfield, the US envoy to the UN, said: “Certain key edits were ignored, including our requests to add a condemnation of Hamas, and we did not agree with everything in the resolution. For that reason we were unfortunately not able to vote yes. However, as I’ve said before, we fully support some of the critical objectives in this non-binding resolution.”

Her claim that it was non-binding was quickly challenged by UN scholars. Resolutions passed by the UN security council are generally considered legally binding, particularly when the text demands action, reflecting the unequivocal will of the international community. In its own defeated resolution last week, the US had avoided the word “demands”, but rather called it “imperative” to have a ceasefire and a hostage release.

The ceasefire resolution, which succeeded where three earlier attempts had failed, was drafted by the 10 elected members of the council: Algeria, Ecuador, Guyana, Japan, Malta, Mozambique, Republic of Korea, Sierra Leone, Slovenia and Switzerland. Several of their representatives bemoaned the long deadlock between the major powers that had paralysed the security council over Gaza since October.

The UK abstained on the three earlier ceasefire resolutions but voted in favour of Monday’s text. In explaining the vote, the British ambassador, Barbara Woodward, did not make clear what had allowed the change in the UK’s vote. British officials, however, have said that Downing Street policy was not to adopt positions at the UN that were directly at odds with Washington.

“This resolution needs to be implemented immediately,” Woodward said, on being asked if the text was binding. “It sends a clear council message, a united council message, and we expect all council resolutions to be implemented.”

Thomas-Greenfield had also insisted that the wording of the resolution “means a ceasefire of any duration must come with the release of hostages”. But the wording of the resolution, intensely debated over the weekend, demands a ceasefire and a hostage release in parallel. It does not make one conditional on the other.

The security council resolution also “emphasises the urgent need” for the expansion of the flow of humanitarian assistance into Gaza and for civilians to be protected, in acknowledgement of the huge civilian death toll and the UN warnings of famine.