The Senate approved on Wednesday a joint resolution to remove US forces from Yemen, except those fighting Al Qaeda, despite a threat of a veto from US President Donald Trump.
The resolution passed by 54 votes to 46 and called to “direct the removal of US Armed Forces from hostilities in the Republic of Yemen that have not been authorised by Congress".
Independent Senator Bernie Sanders, Republican Mike Lee and Democrat Chris Murphy led the fight to pass the resolution, in the first time Congress has tried to block a president on war.
Now it will go to the House of Representatives where it is also expected to pass.
The bill says hostilities include helping the Arab Coalition to choose air strike targets, sharing intelligence and aerial refuelling.
Washington ended refuelling missions in November. Saudi Arabia said that US assistance was no longer needed.
The bill also directs the President "to remove US Armed Forces from hostilities in or affecting the Republic of Yemen, except those engaged in operations directed at Al Qaeda or associated forces", within 30 days after the resolution's enactment.
The bill quotes existing laws to make the case for Congressional oversight in the war, including the War Powers Resolution from 1973, and the State Authorisation Acts of 1984 and 1985.
But the resolution will probably be struck down by Mr Trump's first veto since he took office.
The White House attacked the bill yesterday, saying that it “would harm bilateral relationships in the region" and "negatively affect our ability to prevent the spread of violent extremist organisations".
Congress would need more than two thirds of the votes to override a veto, which is not expected in this case.
The Trump administration also said it would “establish bad precedent for future legislation by defining 'hostilities' to include defence co-operation such as aerial refuelling for the purposes of this legislation".
Mr Sanders, who is running for the Democratic nomination for President in 2020, called the Yemen war “harmful to our national security and the security of the region".
Opponents of the resolution warned of the Iranian threat in Yemen and its growing support for the Houthis.