The bipartisan push to end U.S. support for the Saudi-led war in Yemen has gained political momentum but faces resistance from the No. 2 Democratic lawmaker in the House, Rep. Steny Hoyer, D-Md.

H.Con.Res.81, the resolution sponsored by Reps. Ro Khanna, D-Calif.; Walter Jones, R-N.C.; Mark Pocan, D-Wisc.; Tom Massie, R-Ky.; and 34 other lawmakers, utilizes a provision of the War Powers Act to swiftly terminate U.S. military assistance for the Saudi-led war effort.

Several activists working to build support for the measure have told The Intercept that Republican caucus leaders and Hoyer, the minority whip, are pressuring lawmakers to avoid sponsoring the legislation.

The political opposition comes as new reports reveal that the Saudi-backed military coalition’s constant bombing of Yemen’s civilian infrastructure, as well as the blockade of Yemen’s primary port, has resulted in one of the worst humanitarian crises of the 21st century. Nearly a quarter of the country’s 28 million residents are living in starvation and thousands, mostly children, are dying of cholera, as shipments of food and medicine have been prevented from reaching Yemen.

I’ve been making the rounds on the Hill, and I’ve heard from Hill offices that behind the scenes, House Democrats are being urged by Congressman Hoyer’s office not to sign on to H.Con.Res.81,” said retired Col. Lawrence Wilkerson, who was former U.S. Secretary of State Colin Powell’s chief of staff. Wilkerson, who opposes the war, has been working with other human rights activists to end American involvement in the conflict.

Katie Grant, a spokesperson for Hoyer’s office, did not deny the congressman’s opposition to the resolution and instead issued a statement indicating that negotiations are ongoing. “Whip Hoyer is working with Rep. Khanna, Republican and Democratic leadership, and the Foreign Affairs Committee to find a way forward,” Grant said.

Even as Hoyer works to dissuade lawmakers to cosponsor the resolution, he is also trying to avoid a special Rules Committee decision by House Republicans that would effectively kill the legislation before it receives a vote, according to a legislative aide with firsthand knowledge of the deliberations who is not authorized to speak publicly on the subject. As it is currently written, the resolution has privileged status under the War Powers Act of 1973, meaning it will make it to the floor for a vote regardless of what happens at the committee. Anti-war advocates are concerned that the Republican leadership will strip the legislation of its privileged status, which means the resolution will have no chance.

Since the outbreak of war in March 2015, the U.S. has provided an array of assistance to the Saudi Arabia and United Arab Emirates-led assault on Houthi militias in Yemen. Support has included intelligence sharing, refueling flights for coalition warplanes, and the transfer of American-made cluster bombs, rockets, and other munitions used against targets in Yemen.

The resolution to end U.S. support for the war spotlights an ideological divide within the Democratic Party on foreign policy. Hoyer voted for the war in Iraq and is generally seen as one of the more hawkish members of the party.

On Monday, the Congressional Progressive Caucus endorsed the Yemen resolution, calling for a swift end to “the senseless suffering of Yemeni victims of the U.S.-Saudi military campaign, millions of whom are on the brink of starvation.”

While the war in Yemen is rooted in tribal conflict, it has drawn regional powers, each with its own political agenda and allies. The Houthis have received support from Iran, the regional adversary of both Saudi Arabia and the United Arab Emirates. Israel, also an opponent of Iran, reportedly offered military technology to Saudi Arabia for its conflict with Houthi rebels.

Advocates are concerned that lawmakers are being pressured against ending the conflict for fear of alienating U.S. allies in the region. Saudi Arabia, notably, has pledged to purchase $100 billion in weapons from American contractors — including companies such as Lockheed Martin and Boeing that have wide sway on Capitol Hill.

The concurrent resolution compels President Donald Trump to remove U.S. military forces from the hostilities in Yemen within 30 days. The resolution draws upon a provision of the War Powers Act, passed through a congressional override over former President Richard Nixon’s veto, designed to rein in unauthorized foreign wars.

The Obama and Trump administrations have justified U.S. involvement in the wider region under the 2001 Authorization for Use of Military Force, a broad piece of legislation that allows U.S. military action against those responsible for the September 11 terrorist attacks — namely Al Qaeda. Human rights observers argue that relying on the AUMF in the current conflict would be absurd. Militias aligned with Al Qaeda’s affiliate in Yemen are fighting alongside the Saudi-led coalition against the Houthis, meaning the United States is in league with the faction Congress authorized the military to fight.

The resolution, notably, would not impede U.S. military against against Al Qaeda in Yemen.

But lawmakers have not openly debated the legality of the Yemen War with an on-the-record vote, despite growing opposition from both sides of the aisle to American support for the Saudi-led coalition.

In addition to the resolution, there is another legislative track that may change U.S. policy in the region. In July, lawmakers approved an amendment from Rep. Warren Davidson, R-Ohio, to the National Defense Authorization Act to defund U.S. military operations in Yemen. But the measure was approved through a voice vote, meaning no recorded votes were taken.

Advocates were elated that such a measure passed, but remain wary that the amendment could easily be stripped through the House-Senate conference committee without any debate or legislative fingerprints. The measure, they worry, was designed to placate growing opposition to the war in Yemen without forcing members to take a vote. The amendment could be deleted behind closed doors before the bill is signed by the president.

Unlike the Davidson amendment, the War Powers Resolution would require a recorded floor vote and open debate around the measure.

Advocates for the resolution are hopeful that senior Democratic lawmakers break ranks and co-sponsor the bill.

Democratic Leader Rep. Nancy Pelosi, D-Calif., has signaled support for the resolution, advocates for the bill say. Pelosi’s office did not respond to a request for comment.

Rep. Joe Crowley, D-N.Y., the fouth ranking Democrat in the House, said he “is concerned about what is happening in Yemen and hopes Republicans will allow debate on the floor,” but he stopped short of saying he would co-sponsor the resolution. Crowley “will continue to review this important issue,” his spokesperson told The Intercept.

Several activists we spoke to expressed concern that Rep. Adam Smith, D-Wash., the ranking Democrat on the House Armed Services Committee, would oppose the resolution, given that he was one of the few Democrats to vote against a measure to ban cluster bombs in Yemen. But Smith told The Intercept that he is opposed to the “U.S. taking sides in the civil war in Yemen.”

Smith noted that he has not yet backed the resolution because he is working to make sure similar language to end the conflict is included in the NDAA. Smith acknowledged that Hoyer’s office has opposed the resolution but emphasized that he is not personally against it.

“Once we’re done with the conference report in the NDAA, I would think that I would, yes,” Smith said of his intention to co-sponsor the Khanna-Massie resolution.

Over the weekend, 65 human rights and activist groups signed a letter to Congress urging support for the resolution.

“This war of attrition has been waged using U.S. weaponry, military support, and personnel without congressional authorization for far too long,” the letter declares. “As the Trump Administration has consistently ignored human rights and civilian harm in its national security decisions, and looks to take a more aggressive posture in the region, Congress must send a clear signal that U.S. military involvement in Yemen’s civil war requires congressional authorization.”

Top photo: A Yemeni soldier stands on the debris of a house, hit in an airstrike on a residential district, in the capital Sana’a on Aug. 26, 2017.