A Democratic congressman from Illinois has introduced legislation that would bar Israel from using American-supplied weapons in Gaza and the West Bank unless it can demonstrate compliance with a specific set of conditions — marking one of the most detailed attempts yet by a US lawmaker to attach accountability to military aid that has flowed to Israel largely without restriction since October 2023.

Rep. Sean Casten introduced the Ceasefire Compliance Act of 2026, a bill that creates a recurring certification process requiring the Secretary of State — coordinating with the Defense Department and the Director of National Intelligence — to verify that Israel meets defined standards before US-origin defense articles can be used in either territory.

The certification must be completed within 30 days of the bill’s enactment and repeated every 90 days thereafter. If Israel is found to be in violation, the bill triggers an automatic ban on authorizing new transfers for end use in Gaza or the West Bank, and bars previously delivered US weapons from being deployed there.

The legislation also establishes an end-use monitoring group and requires 60-day reporting on whether American-origin military equipment is actively being used in either territory — a transparency mechanism that currently does not exist in any enforceable form.

The bill includes carve-outs for missile defense support and authorized humanitarian assistance, and a five-year sunset clause.

Whether it advances in a Congress that has repeatedly refused to condition aid to Israel is an open question. But its introduction signals something important: a growing acknowledgment, even within the Democratic Party, that the United States bears legal and moral responsibility for what its weapons are being used to do in Gaza — and that the current arrangement, in which billions in military aid flows with no accountability mechanism, is no longer defensible.