The UK government will consider suspending arms export licences to Israel if Benjamin Netanyahu goes ahead with a potentially devastating ground offensive on the Palestinian city of Rafah in southern Gaza. As the humanitarian situation in Gaza has worsened, diplomatic pressure has been mounting on the UK to follow other countries and suspend arms exports to Israel. Ministerial sources said that while no decision had been made about a suspension of arms export licences, the UK had the ability to respond quickly if the legal advice to ministers said that Israel was in breach of international humanitarian law. The UK has joined other allies in pressuring Israel to avoid a ground offensive in Rafah. In a letter to the foreign affairs select committee about arms export controls to Israel published on Tuesday, David Cameron, the foreign secretary, said he could not see how an offensive in Rafah could go ahead without harming civilians and destroying homes. In the Commons, the UK foreign minister Andrew Mitchell underscored that an offensive in Rafah represented a red line for the UK government, telling MPs on Wednesday that the UK was urging the Israeli government not to launch an attack that could have “devastating consequences”. At a meeting in Geneva on Wednesday on the Arms Trade Treaty, UK officials were accused by Palestinian diplomats of breaking the treaty by refusing to rescind arms sales after the International Court of Justice ruled that Israel must ensure its forces did not commit acts of genocide against Palestinians in Gaza. Palestinian representative Nada Tarbrush warned “a ground incursion in Rafah will lead to mass killings on an even greater scale than the atrocities we have seen in recent months”, adding that when the history books come to be written no one in the west can pretend they did not know of the destruction. British officials told the meeting: “We can and do respond quickly and flexibly to changing and fluid situations.” An article in the treaty obligates states not to authorise any transfer of conventional weapons if they know that those weapons will be used to commit acts of genocide or crimes against humanity. In the Commons, Mitchell accused Hamas of cynical tactics, but told MPs: “We must recognise that Israeli soldiers will only be able to reach hostages or the Hamas leadership at an incredible cost to innocent lives. We share Israel’s desire to end the threat from Hamas and ensure it no longer exerts control over Gaza, but the UK and our partners say Israel must reflect on whether such a military operation is wise – is it counterproductive to its long-term interest?” In his letter to the UK foreign affairs select committee, Cameron went out of his way to signal Rafah’s importance, expressing “deep concern” about the prospect of an offensive. “We do not underestimate the devastating humanitarian impacts that a full ground offensive, if enacted, would have in these circumstances,” he said. He added: “We continue to urge Israel to ensure that it limits its operations to military targets and take all possible steps to avoid harming civilians and destroying homes.” However, in the case of a potential military offensive in Rafah, he said: “It is difficult to see how this could be achieved. Civilians are not able to cross into Egypt nor are they able to return northwards.” Privately, British officials believe Israel is intent on an attack on Rafah. The UK is not due to disclose the arms export licences granted to Israel in the final quarter of last year until much later this year. In 2022 the UK granted 114 standard export licences to Israel worth £42m. Although Cameron in his letter to the chair of the foreign affairs select committee, Alicia Kearns, said “you are asking the right questions”, he did not answer the committee’s request to reveal how many export licence applications have been referred to ministers. Earlier this month The Hague district court ordered the Dutch government to stop the export of F-35 fighter jet parts to Israel within seven days due to the risk of serious violations of international humanitarian law and referred to the ATT and EU policy.