The Senate on Thursday ordered the Pentagon to cease its military involvement on behalf of Saudi Arabia in the Yemeni civil war. It marked the first time since the 1973 passage of the War Powers Act that the Senate has ordered the executive branch to end an unauthorized military campaign.

The Senate passed, 56-41, the joint resolution, as amended, that would direct the president to remove U.S. armed forces from hostilities in or affecting the Republic of Yemen, except forces engaged in operations directed at Al Qaeda or associated forces, within 30 days of the joint resolution’s adoption of the joint resolution, unless and until a declaration of war or specific authorization of such use of force has been enacted.

The vote was widely viewed as a proxy vote to rebuke Saudi Arabia, whose war against Yemen has led to a humanitarian crisis there, and whose culpability in the killing of dissident Saudi journalist Jamal Khashoggi this year has roiled Congress. It was also viewed as a rebuke of President Donald Trump, who has stood by the Saudis.

Sen. Christopher S. Murphy, D-Conn., who sponsored the resolution with Sens. Bernie Sanders, I-Vt., and Mike Lee, R-Utah, said the vote showed the magnitude of people fed up with Saudi Arabia’s conduct.

“With this vote, Saudi Arabia just lost the support of Congress for their disastrous war in Yemen. A bipartisan majority spoke with one voice that the status quo is over and we will no longer accept the war crimes being committed in our name,” said Murphy. “The momentum is on one side, and it’s only growing. Congress has woken up to the reality that the Saudi-led Coalition is using U.S. military support to kill thousands of civilians, bomb hospitals, block humanitarian aid, and arm radical militias. The Saudis are important partners, but they need to realize that our partnership is not a blank check for them to fund extremists and murder civilians.”