A Democratic congressional source told The Intercept on Friday that the administration was using the measure to clear a backlog of more than 20 proposed arms sales to Saudi Arabia and the UAE, many of which would be blocked if they came to a vote in the Senate.

The Trump administration chose the Friday afternoon before Memorial Day weekend to invoke an obscure state-of-emergency provision that would allow it to sell billions of dollars in weapons to Saudi Arabia and the United Arab Emirates without giving Congress a chance to block the sale.

Under the 1976 Arms Export Control Act, the State Department must notify Congress 30 days before concluding an arms sale, which gives Congress the chance to vote on halting the weapons transfer. Under the rarely used provision, however, the president can certify that “an emergency exists” and that an immediate transfer is necessary for “the national security interests of the United States.”

In a statement on Friday, Sen. Bob Menedez, the top Democrat on the Senate Foreign Relations Committee, said that in notifying Congress of its plans, the Trump administration had “described years of malign Iranian behavior but failed to identify what actually constitutes an emergency today.”

Since 2015, Saudi Arabia and the UAE have been involved in an intervention in Yemen, aimed at restoring the former president, Abdu Rabbu Mansour Hadi, to power. The intervention’s U.S.-supported bombing campaign has come under heavy criticism for repeatedly destroying civilian structures, including homes, markets, factories, water treatment plants, schools, and hospitals.

Menendez previously held up $2 billion in sales of precision-guided bombs to Saudi Arabia and the UAE over human rights concerns.

In the past, presidents who invoked the provision have been able to point to time-sensitive emergencies that justified going around Congress. In the days after Saddam Hussein invaded Kuwait in 1990, for example, President George H.W. Bush invoked it to transfer M60 tanks and F-15 aircraft to Saudi Arabia to secure its northeastern border.

Connecticut Democratic Sen. Chris Murphy, who warned days ago that the Trump administration would try to circumvent Congress, said that President Donald Trump is only using the loophole because he knows he cannot sell weapons to Saudi Arabia any other way.

“There is no new ‘emergency’ reason to sell bombs to the Saudis to drop in Yemen, and doing so only perpetuates the humanitarian crisis there,” Murphy said in a statement Friday.