Washington (CNN) Sen. Chris Murphy warned Wednesday that President Donald Trump is considering using an "obscure loophole" in arms control law that would allow his administration to sell a new batch of bombs to Saudi Arabia without congressional approval.

Circumventing Congress in order to sell munitions to the Saudis "would be a complete abuse of power," Murphy told CNN, adding that the administration could put its plan in motion as early as this week.

"Arms control law allows Congress to reject a sale to a foreign country. But Trump would claim the sale constitutes an 'emergency' which means Congress can't take a vote of disapproval. It would go through automatically," the Connecticut Democrat and member of the Senate Foreign Relations Committee said in a tweet.

"To state the obvious, there is no new emergency reason to sell bombs to Saudi Arabia to drop in Yemen. The Saudis been dropping the bombs on civilians, so if there is an emergency, it's a humanitarian emergency caused by the bombs we sell the Saudis," he added.

Asked about the issue Wednesday, Murphy said he wanted to alert his colleagues that the move was "potentially happening" and hoped his fellow lawmakers would pressure the administration to stop it.

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