The international criminal court has issued arrest warrants for the Israeli prime minister, Benjamin Netanyahu, the country’s former defence minister Yoav Gallant and the Hamas military leader Mohammed Deif for alleged war crimes relating to the Gaza war.

It is the first time that leaders of a democracy and western-aligned state have been charged by the court, in the most momentous decision of its 22-year history.

Netanyahu and Gallant are at risk of arrest if they travel to any of the 124 countries that signed the Rome statute establishing the court. Israel claims to have killed Deif in an airstrike in July, but the court’s pre-trial chamber said it would “continue to gather information” to confirm his death.

The chamber ruled there were reasonable grounds to believe Netanyahu and Gallant bore criminal responsibility as co-perpetrators for “the war crime of starvation as a method of warfare; and the crimes against humanity of murder, persecution, and other inhumane acts”.

The three-judge panel also said it had found reasonable grounds to believe Deif was responsible for crimes against humanity and war crimes including murder, torture, rape and hostage taking relating to the Hamas attack on Israel on 7 October 2023 in which fighters killed more than 1,200 people, mostly Israeli civilians, and kidnapped 250.

The US criticised the move, with Joe Biden describing the warrants in a statement on Thursday night as “outrageous”.

“Let me be clear once again: whatever the ICC might imply, there is no equivalence – none – between Israel and Hamas. We will always stand with Israel against threats to its security.”

Netanyahu’s office denounced the chamber’s decision as “antisemitic”.

“Israel utterly rejects the false and absurd charges of the international criminal court, a biased and discriminatory political body,” the office said in a statement, adding that “no war is more just than the war Israel has been waging in Gaza”.

The statement pointed to an investigation into accusations of sexual misconduct against the ICC prosecutor Karim Khan who sought the charges against the three men in May. Khan, 54, has denied the allegations and said he will cooperate with the investigation.

Netanyahu said in a video statement: “No outrageous anti-Israel decision will prevent us – and it will not prevent me – from continuing to defend our country in every way. We will not yield to pressure.”

The US national security council issued a statement “fundamentally” rejecting the court’s decision. “We remain deeply concerned by the prosecutor’s rush to seek arrest warrants and the troubling process errors that led to this decision,” the statement said, without any detail of the alleged errors.

“The United States has been clear that the ICC does not have jurisdiction over this matter. In coordination with partners, including Israel, we are discussing next steps.”

The US has previously welcomed ICC war crimes warrants against Vladimir Putin and other Russian officials for atrocities committed in Ukraine, exposing the Biden administration to accusations of double standards from many UN members, particularly from the global south.

Netanyahu can expect more resounding support from the incoming Donald Trump administration. During his first term, in 2020, Trump imposed US sanctions on the ICC, aimed at court officials and their families. The then secretary of state, Mike Pompeo, made clear the sanctions were imposed because the ICC had begun investigating the actions of the US and its allies in Afghanistan, as well as Israeli military operations in the occupied territories.

The UK is expected to agree to the request to arrest Netanyahu if he came to Britain, although Downing Street refused to directly confirm this, saying only that it would “respect” the court’s independence. A spokesperson said a UK-based court procedure would be needed to approve any request.

The panel said the full version of the warrants against Netanyahu and Gallant were secret “in order to protect witnesses and to safeguard the conduct of the investigations”, but the judges released much of their reasoning. This focused on the obstruction of the supply of humanitarian aid into Gaza, which it judged to be deliberate.

“The chamber considered that there are reasonable grounds to believe that both individuals intentionally and knowingly deprived the civilian population in Gaza of objects indispensable to their survival, including food, water, and medicine and medical supplies, as well as fuel and electricity,” the written ruling said.

The warrants were broadly welcomed by human rights groups. Balkees Jarrah, an associate international justice director at Human Rights Watch, said they would “break through the perception” that certain individuals were beyond the reach of the law.

“Whether the ICC can effectively deliver on its mandate will depend on governments’ willingness to support justice no matter where abuses are committed and by whom,” Jarrah said. “These warrants should finally push the international community to address atrocities and secure justice for all victims in Palestine and Israel.”

Israel has denied committing war crimes in Gaza and has rejected the jurisdiction of the court. However, the pretrial chamber noted that Palestine had been recognised as a member of the court in 2015, so the ICC did not require Israeli approval to investigate crimes on Palestinian territory.

The chamber also rejected an Israeli appeal for the warrants to be deferred, saying the Israeli authorities were informed of an earlier ICC investigation in 2021, and at that time, “Israel elected not to pursue any request for deferral of the investigation”.

An ICC statement said of Deif that “the chamber found reasonable grounds to believe that Mr Deif … is responsible for the crimes against humanity of murder, extermination, torture and rape and other form of sexual violence, as well as the war crimes of murder, cruel treatment, torture, taking hostages, outrages upon personal dignity, and rape and other forms of sexual violence”.

Khan had sought warrants for two other senior Hamas figures, Yahya Sinwar and Ismail Haniyeh, but they were killed in the conflict. Israel’s claim to have killed Deif has been neither confirmed nor denied by Hamas.

Benny Gantz, a retired general and political rival to Netanyahu, condemned the ICC’s decision, saying it showed “moral blindness” and was a “shameful stain of historic proportion that will never be forgotten”. Yair Lapid, another opposition leader, called it a “prize for terror”.

The warrants have been issued at a sensitive moment for Khan, in the face of an investigation of claims of sexual misconduct. The inquiry will examine the allegations against the prosecutor, which, the Guardian reported last month, include claims of unwanted sexual touching and “abuse” over an extended period, as well as coercive behaviour and abuse of authority. The alleged victim, an ICC lawyer in her 30s, has previously declined to comment.

The arrest warrants could increase the external pressure on Netanyahu’s government as the US seeks to broker a ceasefire between Israel and Hamas, but could well strengthen the prime minister’s political position in Israel in the short term, as most Israelis reject the ICC’s jurisdiction, regarding it as interference in their country’s internal affairs.

Biden has said he does not believe Netanyahu is doing enough to secure a ceasefire, after the Israeli leader vowed not to compromise on Israeli control over strategic territory inside Gaza. Netanyahu has accused Hamas of failing to negotiate in good faith.