US senators have delivered a stunning blow to US President Donald Trump as they voted to withdraw support for the Saudi-led bombing and war against Yemen.

They ignored appeals from Secretary of State Mike Pompeo and Defence Secretary Jim Mattis who claimed that dropping support for the devastating campaign would worsen the situation in Yemen.

The motion received support from both Republicans and Democrats during Wednesday’s closed session with senators voting 63-37 to take the it forward.

“It’s time to send Saudi Arabia a message, both on its violation of human rights and the incredible humanitarian catastrophe it’s creating in Yemen,” Democrat Senator Bob Menendez said.

Senior Republicans are also unhappy at the failure of US President Donald Trump to take firm action against Saudi Arabia in the wake of the murder of journalist Jamal Khashoggi in the Istanbul consulate last month.

However Mr Pompeo restated Mr Trump’s view that “there is no direct reporting connecting the Saudi crown prince to the order to murder Jamal Khashoggi.”

Senate foreign relations committee chair Republican Senator Bob Corker said: “We have a problem here. We understand that Saudi Arabia is an ally, of sorts, and a semi-important country. We also have a crown prince that’s out of control.”

The passing of the motion means there will now be a full debate on the US relations with Saudi Arabia in the Senate.

The House of Representatives has voted down similar measures in the past, but Democrats will hold a majority after the results of the midterm elections when it reconvenes in January. 

Saudi Arabia’s deadly war on Yemen started in March 2015 and has been backed by US military and tactical support, including through the supply of weapons.

More than 50,000 have been killed during the bombing with allegations of war crimes after civilians and infrastructure have been targeted. 

The UN warned that Yemen stands on the brink of the world’s worst global famine for 100 years with aid agencies saying that “14 million people are at risk of starving to death in Yemen if the parties to the conflict and their supporters do not change course immediately.”

Save the Children said in a report that an estimated 85,000 children under the age of five have died from extreme hunger or disease since the war began.