Saudi Arabia has been criticized internationally for the high number of civilian deaths from airstrikes launched by a Saudi-led coalition against the Houthi political opposition faction in Yemen.
Citing Saudi Arabia's human rights record in the ongoing bombing campaign, Senators Rand Paul (R-KY), Mike Lee (R-UT), Al Franken (D-MN), and Chris Murphy (D-CT) co-sponsored the bill to block the sale.
The senators believe that Saudi Arabia continues to finance Islamic schools around the world that teach extremist versions of Islam and prepare students to join terrorist organizations such as al-Qaeda and Daesh.
Murphy recently noted in a Twitter message that he had never before seen so many senators go on record as supporting a rethink of the US-Saudi relationship.
A House version of the bill was introduced on Wednesday, co-sponsored by Representatives Ted Lieu and Mike Mulvaney.
The Obama Administration has sold more weapons to the Saudis than any other administration, drawing criticism on the US and contributing to the perception that America is directly financing extremists and participating in war crimes.