But President Trump vows to veto the move as pressure intensifies on UAE-Saudi coalition to end the devastating war.

Washington, DC – The US Senate voted 54 to 46 to block further involvement by the US military in the war in Yemen, where bombings by Saudi Arabia and the UAE, conducted with US weapons, are blamed for causing mass civilian deaths, starvation, and the spread of disease.

“We have the opportunity to take a major step forward in ending the horrific war in Yemen and alleviating that terrible, terrible suffering being experienced by the people in one of the poorest countries in the world,” Senator Bernie Sanders, a Vermont independent, said.

“There is no secret as to why there is a cholera epidemic. It’s because the Saudis bombed the water treatment facilities so the water isn’t clean any more,” said Senator Chris Murphy, a Connecticut Democrat.

Aid groups estimate that as many as 60,000 civilians have been killed in the war and as many as 85,000 children starved to death.

The Senate action sends the resolution back to the House of Representatives, which is expected to approve it a second time after having voted 248 to 177 on February 13 to approve the measure. The resolution is being brought forward under the War Powers Act of 1973, a Vietnam War-era law that asserts Congress’s authority over the deployment of US military power.

“We have been supporting and in some case actively participating in this war,” said Senator Mike Lee, a Utah Republican.

Veto threat

The Trump White House has threatened to veto the joint House and Senate resolution if it reaches the president’s desk. Officials assert the US needs a free hand to support Saudi Arabia in a regional conflict with Iran while pushing for a diplomatic resolution to the Yemen conflict.

Congress would need two-thirds majorities in both chambers to override a presidential veto and have the resolution take effect. So far, backers lack sufficient votes in both the House and Senate to do so.

Republican leaders supporting Trump argued that US legislators’ concerns about the killing of Saudi journalist and US resident Jamal Khashoggi should be addressed separately.

“Concern about Saudi Arabia’s human rights issues should be addressed to the administration and Saudi officials,” said Senate Majority Leader Mitch McConnell, a Kentucky Republican. “That’s what I have chosen to do and what I have asked others to do.”

The resolution would “harm bilateral relationships in the region” and “negatively affect our ability to prevent the spread of violent extremist organisations” such as al-Qaeda and the Islamic State of Iraq and the Levant (ISIL or ISIS) group, the White House said.

The Trump administration argues that, by directing the military to support a US ally, the president is acting within his constitutional authority. The president’s “senior advisers would recommend he veto the joint resolution”, the White House Office of Management and Budget said in a statement of administration policy.

Republicans further warned the measure could lead to US casualties in Saudi Arabia if it prevented the US military from sharing intelligence on the targeting of population centres by Houthi missiles.

Peace talks

United Nations special envoy for Yemen, Martin Griffiths, met with US senators behind closed doors on March 11.

“The UN-led peace talks are our best hope going forward,” and “congressional actions may influence critical peace negotiations”, Senate Foreign Relations Committee Chairman Jim Risch, an Idaho Republican, said in a statement afterwards, supporting the Trump administration’s position.

Others took a different view of Griffiths’ briefing. Senator Tim Kaine, a Virginia Democrat, said he was surprised Griffiths did not urge the Senate to refrain from advancing the resolution.

“Those of us who went to the hearing Monday afternoon fully expected him to tell us, ‘Here’s why I think your resolution is a bad idea.’ He didn’t say that. We asked him directly. He did not say, ‘Please don’t vote for this resolution on Yemen.’ In fact, he said some things that I was very surprised that he said,” Kaine told Al Jazeera.

Griffiths informed senators the Houthis have legitimate issues with the Saudi-backed Yemen government that need to be addressed, and further military action would not advance either side’s interest. He also said the only viable solution in Yemen is a political settlement, according to Kaine.

Congress is increasingly frustrated with the Trump administration’s handling of the US relationship with Saudi Arabia.

Killing Khashoggi

A bipartisan group of senators led by Senator Bob Menendez of New Jersey introduced a bill on February 7 that would impose sanctions on members of the Saudi royal family and others for the killing of Khashoggi. Republican senators Lindsey Graham, Susan Collins and Todd Young are co-sponsors.

US intelligence agencies have concluded Saudi Crown Prince Mohammed bin Salman was involved in Khashoggi’s killing. Trump has refused to respond to demands from Congress that the US reach a determination on Prince Mohammed’s role and impose sanctions under US human rights law, the Global Magnitsky Act.

“All of the evidence suggests that the Saudi crown prince was directly responsible for that murder,” Sanders said.

The Trump administration has not provided senators with any information about meetings Trump’s son-in-law and White House senior adviser Jared Kushner had with Prince Mohammed in Riyadh in late February. Kushner had visited a number of Middle East countries seeking support for the US’s plan for Israel and the Palestinians.

Asked whether senators had been briefed on the White House’s discussions in Riyadh, Kaine told Al Jazeera: “No we have not. Not about Khashoggi. Not about Yemen. Not about discussions about nuclear technology transfer. We have no information.”

The House Oversight Committee has demanded documents from the White House on plans to sell nuclear technology to Saudi Arabia.