RISHI Sunak and Keir Starmer have been urged to “change course” and call for an immediate ceasefire in Gaza amid mounting concern over Israel’s plan for a major military assault on Rafah.

SNP Westminster leader Stephen Flynn has written to the Prime Minister and the opposition leader warning the action threatened by Israeli Prime Minister Benjamin Nentanyahu would "amount to waging a war in the largest refugee camp in the world".

Rafah is a city in southern Gaza where an estimated 1.4 million displaced Palestinians are sheltering and where the UN says a quarter of the population is facing starvation.

Netanyahu said on Saturday plans for an offensive were being worked on adding: “We’re going to do it.”

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First Minister Humza Yousaf joined global leaders and urged the international community to "demand an immediate ceasefire” amid fears over the invasion of Rafah, where Palestinians are packed into sprawling tent camps and UN-run shelters near the border.

Yousaf reacted to a statement by Ireland's Tánaiste and Minister for Foreign Affairs and Defence Micheál Martin that said evidence is “incontrovertible” that Gaza is facing a human catastrophe over the next few days unless sufficient aid flows into the besieged city.

The United States has warned Israel an invasion of Rafah would be a “disaster”, while the EU and UN have also expressed concerns.

UK Foreign Secretary David Cameron has said he is “deeply concerned” but has still only called for an “immediate pause” in fighting rather than an immediate ceasefire.

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Westminster leader Flynn said the assault "cannot be allowed to happen" and warned "only pressing for an immediate ceasefire has any hope of stopping an even more horrific humanitarian disaster unfolding before the watching world".

In his letter, he wrote: “It is important to be crystal clear as to what this intended action will actually mean – it will amount to waging a war in the largest refugee camp in the world.

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“These 1.5 million refugees are now being ordered to evacuate their own homeland by the Israeli army, and they have nowhere else to go. Ten of thousands of innocent civilians – men, women and thousands of children - have already been killed in Gaza.

“I fear those numbers of civilian dead rise rapidly if the attack on Rafah goes ahead.

“Whatever our differences on this issue in the past number of months, whatever the rationale for the UK Government and the Labour Party in opposing an immediate ceasefire until this point, surely now is the time to say enough is enough. 

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“Only pressing for an immediate ceasefire has any hope of stopping an even more horrific humanitarian disaster unfolding before the watching world.

"By acting now, it remains within the power of the international community to press for an immediate ceasefire, stop the imminent assault on Rafah, secure the unconditional release of all the remaining hostages taken by Hamas, and finally put an end to the collective punishment of the Palestinian people.”

Meanwhile, Egypt is threatening to suspend its peace treaty with Israel if troops are sent into Rafah.

Two Egyptian officials and a Western diplomat said on Sunday that fighting there could force the closure of the territory’s main aid supply route. 

Egypt fears a mass influx of hundreds of thousands of Palestinian refugees who may never be allowed to return.

Hamas’s Al-Aqsa television station, meanwhile, quoted an unnamed Hamas official as saying that any invasion of Rafah would “blow up” talks mediated by the United States, Egypt and Qatar aimed at a ceasefire and the release of Israeli hostages.