The Pentagon has also spent more than $10 million on operations across the Middle East since October 7, 2023, according to the document

The US has provided Israel with $21.7 billion in military assistance during the two years of the conflict in Gaza, a new report has said.

The paper by the Costs of War project at Brown University's Watson School of International and Public Affairs was released on Tuesday, the second anniversary of the October 7, 2023 incursion into Israel by Palestinian armed group Hamas, in which 1,200 people were killed and 250 others taken hostage.

Israeli airstrikes and a ground offensive in Gaza, launched in response to the attack, have left more than 67,000 people dead and almost 170,000 injured, according to the Palestinian health authorities. Last month, a UN commission described West Jerusalem's actions as "genocide."

Together with an additional $9.65 to $12.07 billion spent by the Pentagon on military operations in support of Israel in Yemen and elsewhere in the Middle East, the overall US investment in the Gaza conflict amounts to between $31.35 and $33.77 billion, the report stated.

The figure, which was based on open source data, did not include tens of billions of dollars worth of arms to be paid for and delivered in the coming years in line with deals earlier agreed between Washington and West Jerusalem, it added.

The US weapons, including combat aircraft, helicopters, missiles and bombs, "have been central to the Israel Defense Forces (IDF) and Israel Police operations in Gaza, the West Bank, and beyond," the report said.

With their use, Israel "inflicted a devastating humanitarian toll on the people of Gaza," with more than 10% of the Palestinian enclave's population being killed or injured and at least 5.27 million displaced in Gaza and the wider region, it stressed.

Last week, US President Donald Trump, who has maintained the policy of arming Israel pursued by his Democratic predecessor Joe Biden, proposed a prisoner swap agreement between West Jerusalem and Hamas, which he claimed should pave the way for ending the conflict.

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The militant group reacted to the offer by agreeing to release the remaining hostages, but has so far rejected the call to disarm. Despite halting its advance on Gaza City, the IDF has ignored Trump's demand to immediately end airstrikes across the Palestinian enclave.