Labour has announced its biggest step yet in overhauling the UK’s approach to the Middle East, dropping its opposition to an international arrest warrant against Benjamin Netanyahu despite pressure from Washington not to do so. Downing Street announced on Friday that the government would not submit a challenge to the jurisdiction of the international criminal court, whose chief prosecutor, Karim Khan, is seeking a warrant against the Israeli prime minister. The move makes it more likely that the ICC will now grant Khan’s request, in what would be a stunning international rebuke for Israel over the way it has conducted the war in Gaza and put Netanyahu at risk of arrest if he travels abroad. It also reverses months of British policy after the previous government was steadfast in its support of Israel and its desire to stick closely to the US position. Ministers are expected to announce further changes within days, including the results of a review of Israel’s compliance with international law. The foreign secretary, David Lammy, has also signalled that he is considering banning some arms sales to Israel. The prime minister’s deputy official spokesperson said: “On the submission, this was a proposal by the previous government that was not submitted before the election. I can confirm the government will not be pursuing that in line with our longstanding position that this is a matter for the court to decide on. “The government feels very strongly about the rule of law internationally and domestically, and the separation of powers, and I would note the courts have already received a number of submissions on either side and they are well seized of the arguments to make their determination.” She would not be drawn on whether the government had a view on whether a warrant should be issued for Netanyahu’s arrest, saying it was a matter for the courts. Khan announced in May that he was applying for warrants against Netanyahu and his defence minister, Yoav Gallant, for war crimes allegedly committed during the country’s attack on Gaza. He is also pushing for warrants against senior Hamas leaders including Yahya Sinwar, the group’s chief in Gaza, and Mohammed Deif, the commander of its military wing. The former prime minister Rishi Sunak criticised Khan’s decision in May and a month later his government notified the ICC it would lodge a legal challenge to the idea that the court had jurisdiction over Israeli citizens. Israel and the US, neither of which is a signatory to the ICC, had put pressure on the UK to maintain its objection, warning that dropping it could upset peace negotiations being brokered by Washington. Senior Labour figures, however, have long insisted they would respect the independence of the court. Lammy told the Commons in May: “Labour’s position is that the ICC chief prosecutor’s decision to apply for arrest warrants is an independent matter for the court and the prosecutor.” The government’s decision does not necessarily mean Khan’s request will be granted. Dozens of other groups and countries have told the court they want to make submissions both from a pro-Israeli and pro-Palestinian perspective. They include Germany, which has raised concerns that Khan’s case should not be heard while the conflict in Gaza was still raging. The UK’s new position does, however, signal that it will be a stronger critic of Israel under Labour. Lammy announced last week that the UK would join other countries in restoring funding to the UN’s relief agency in Palestine, Unrwa, overturning the previous government’s suspension. He is also preparing to announce the results of a review into whether Israel is breaking international law, and sources have also told the Guardian ministers are considering a partial ban on the sale of weapons to Israel. One source said Lammy was preparing to ban the sale of “offensive” weapons, but not “defensive” ones that could be used to defend Israel against attacks from abroad. The foreign secretary told the Commons last week: “It would not be right to have a blanket ban between our countries and Israel. What is right is for me to consider in the normal way are the issues in relation to offensive weapons in Gaza, following the quasi-judicial process that I have outlined.” Pro-Palestinian organisations have welcomed the UK’s shift in position, while their pro-Israeli counterparts have voiced concerns. Zaki Sarraf, the legal officer of the International Centre for Justice for Palestinians, said: “Respecting the jurisdiction and independence of the ICC is the least the Labour government can do to demonstrate a genuine commitment to justice and accountability.” The Board of Deputies of British Jews and the Jewish Leadership Council issued a joint statement on Friday saying: “We are concerned that the cumulative effect of these announcements, in quick succession, signal a significant shift in policy, away from Israel being a key UK ally. This would not only be a strategic error but a moral one.”