WASHINGTON — The House of Representatives sent President Donald Trump a stinging rebuke Wednesday when they used the War Powers Act to cut off any U.S. military support for the ongoing civil war in Yemen.

The measure had remained bottled up by GOP leaders for years, but it sailed through by a vote of 248 yeas to 177 nays and is now on its way to the Senate, where supporters are also confident the measure will pass.

“This is a historic vote. It’s a culmination of years of effort,” Rep. Ted Lieu (D-Calif.) told VICE News at the Capitol. “The civil war has caused massive humanitarian suffering to the Yemeni people, and you have bipartisan members of Congress who want to reduce that suffering.”

Beyond Yemen, if the resolution passes the Senate, it will be Congress’ first use of the War Powers Resolution of 1973 to reassert its authority over the use of U.S. military in foreign conflicts, which could force President Trump to seek congressional approval to deploy U.S. forces abroad in the future. The White House has already threatened to veto the measure.

Lieu said the measure is just a first step. He argues the U.S. still needs to help the two sides negotiate an end to the civil war, and make sure humanitarian aid isn’t blocked from reaching the millions of men, women and children who are suffering from starvation.

“Yemen is very complex. There are multiple bad things happening. One is the targeting and hitting of innocent civilians, which are war crimes,” he said.

Reining in Trump

Supporters are also hoping the vote alone will help change the dynamics on the ground in Yemen, as well as the Middle East.

“This is going to put huge pressure on the Saudis to come to the peace table,” Rep. Ro Khanna (D-Calif) told VICE News just off the House floor.

In December the Saudis agreed to a temporary one-month ceasefire after the Senate overwhelmingly passed a similar resolution, but former Speaker Paul Ryan never allowed that measure to come up for a vote in the House.

“At the end of the day, presidents come and go, but the Congress stays. And nations that have stable relationships with the United States have good relationships with Congress,” Khanna said. “So if this is not a wakeup call for the Saudis, I don’t know what would be.”

The measure maintained bipartisan support, but its Republican critics accuse Speaker Nancy Pelosi and her new Democratic majority in the House of playing politics with the War Powers Act.

“They want to change the rules now that President Trump is the president, but they didn’t want to change a darn thing when Barack Obama was president,” Rep. Scott Perry (R-Pa.) told VICE News in the basement of the Capitol.

For critics ending U.S. military support in Yemen will only bolster Iran and give them and their allies a greater foothold in the region.

“We have a choice between Iran and Saudi Arabia in Yemen. Arguably we have problems with each one of them, but easily one is much worse than the other toward the United States’ interests,” Perry said. “So while this is an imperfect situation, you’ve got to stick with the policy that’s working for us right now.”

Who declares war?

But for the bill’s supporters, GOP leaders were merely trying to shield their members from a tough vote for years, while also tamping down the voices of the American people and their elected representatives in Congress.

“The most important work that we do as members of Congress is to have the opportunity to have debates like this about war and peace and the role that the U.S. military should play, so I’m glad that we’re finally at this moment,” Rep. Ted Deutch (D-Fla.) told VICE News just off the House floor.

The Yemeni conflict has only gotten more attention since Washington Post columnist Jamal Khashoggi was brutally slaughtered in October, allegedly by top Saudi security officials. While the CIA has concluded that Saudi Crown Prince Mohammed bin Salman played a role in the slaying, President Trump has rejected those assessments and sided with the denials of Saudi leaders.

Most senators on both sides of the aisle have been up in arms over the president’s handling of the killing, and many were upset last week when the administration failed to send Congress a required assessment on the slaying.

“I certainly think they should have issued the report – the law requires it,” Sen. Marco Rubio (R-Fla.) told reporters at the Capitol. “I personally believe, [based] on anything I know, that you can fairly say that the crown prince either knew about it or ordered it.”

Sen. Chris Murphy (D-Conn.) predicts the bill will sail through the Senate and head to Trump’s desk, forcing the administration to decide whether to follow through on their threatened veto.

“It’s a big deal. The House has never taken this vote,” Murphy said. “It will then pass the Senate and the president will then have a decision to make.”