US President Joe Biden has issued a memorandum saying countries receiving American weapons must adhere to international law.
The executive order requires foreign governments receiving military aid to provide written assurances that they are abiding by the laws of war.
The move comes after Mr Biden admitted that the country had gone “over the top” in its response in Gaza.
BBC News says since 1950, Israel has received more US military aid than any other nation.
In the memorandum, President Biden said “credible and reliable written assurances” must be provided to the US by foreign governments that receive American weapons to ensure they are used in accordance with international law.
Foreign governments must also provide assurances that US humanitarian aid is being delivered to civilian populations caught in a conflict.
All 100 countries receiving US weapons must sign the assurances in the next 180 days, but those involved in active conflicts, including Israel, have just 45 days to reply.
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