Story highlights Congress was notified last week of the sale, which was negotiated under Obama

The legislative branch has 30 days to vote to block the sale under a quirky procedure

(CNN) A bipartisan Senate trio is planning to force a vote next month on a small sliver of the $110 billion in arms sales to Saudi Arabia that President Donald Trump announced last week.

Republican Sen. Rand Paul of Kentucky and Democratic Sens. Chris Murphy of Connecticut and Al Franken of Minnesota introduced a resolution Thursday to block a proposed arms sale to Saudi Arabia of about $500 million that includes precision-guided munitions.

Congress was notified last week of the sale, which was initially negotiated under the Obama administration, and the legislative branch has 30 days to vote to block the sale. Under a quirky procedure established by the Arms Export Control Act of 1976, the senators have the ability to force a floor vote on the resolution.

While the vote would be over just a fraction of the arms that the Trump administration has now signed off on selling to the Saudis, the senators are seeking to make it a symbolic debate on the overall agreement.

They are objecting to Saudi Arabia's role in Yemen's civil war , where the Saudi-led bombing campaign against the Houthis is accused of targeting civilians, arguing that the weapons being sold to the Saudis by the US will lead to greater civilian casualties.

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