The US senate has voted by a big bipartisan margin to move forward with legislation calling for an end to America’s involvement in the Saudi-led war in Yemen.

The 63-37 majority sent a strong signal that politicians in congress want to punish Saudi Arabia for its role in Jamal Khashoggi’s murder, and rebuke the Trump administration for its tepid response.

Mike Pompeo, secretary of state, and secretary of defence James Mattis both visited the senate on Capitol Hill on Wednesday to urgently lobby against the resolution, which would call for an end to US military assistance for the conflict that human rights advocates say is wreaking havoc on Yemen and its civilians.

The vote showed a significant number of Republicans were willing to break with Mr Trump to express their deep dissatisfaction with the US president, Saudi Arabia and Mohammed bin Salman, the country’s crown prince.

Donald Trump, by refusing to blame Mr Bin Salman, has made it clear he does not want to torpedo Washington’s longstanding relationship with Riyadh over the journalist’s death.

Senator Chris Murphy, who co-sponsored the bill, said on Twitter: "I’ve been at this for 3 years, and I am blown away by this. By a big bipartisan margin, 63-37, the Senate just voted, for the first time, to move forward with a debate on ending American involvement in the Yemen war.

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Mr Murphy thanked fellow senators Bernie Sanders and Mike Lee for also co-sponsoring the bill.

US intelligence officials have concluded Mr Bin Salman must have at least known of the plot, but Mr Trump has equivocated over who is to blame.

Khashoggi, who lived in the US, was murdered in Saudi Arabia’s consulate in Istanbul last month in what US officials described as an elaborate plot. The Washington Post writer was a prominent critic of the crown prince.

Echoing Mr Trump's public comments on the killing, Mr Pompeo said after Wednesday's briefing with senators that there was "no direct reporting" connecting the crown prince to the murder, and Mr Mattis said there was "no smoking gun" making the connection.

Mr Pompeo argued the war in Yemen would be "a hell of a lot worse" if the US were not involved.

Wednesday's procedural vote sets up a debate on the resolution next week. It would be largely a symbolic move, however, as House Republican leaders have given no indication they would take up the war powers measure before the end of the year – the end of the current congress.

Several senators said they were angry about the absence of CIA director Gina Haspel from the pre-vote briefing.

New Jersey senator Bob Menendez, the top Democrat on the senate foreign relations committee, speculated Ms Haspel did not attend because she "would have said with a high degree of confidence the crown prince of Saudi Arabia was involved in the murder of Jamal Khashoggi".

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Lindsey Graham, the South Carolina Republican who is often strongly allied with Mr Trump, voted to move forward with the resolution and said he would insist on a briefing from Mr Haspel.

He even threatened to withhold his vote on key measures if that did not happen and declared: "I'm not going to blow past this."

CIA press secretary Timothy Barrett said that no one kept Ms Haspel away from the briefing.

He said the CIA had already briefed the senate intelligence committee and senate leaders and "will continue to provide updates on this important matter to policymakers and congress".

In another explanation, a White House official said Ms Haspel decided not to participate in part because of frustration with lawmakers leaking classified intelligence from such settings.

The official spoke on the condition of anonymity to discuss internal matters.

The procedural vote received more Republican support than had been expected after the resolution fell six votes short of passage earlier this year.

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Foreign relations committee chairman Bob Corker, a Republican senator from Tennessee, said in the past he had "laid in the railroad tracks to keep us from doing things that I believe are against our national interest as it relates to Saudi Arabia".

But he said he believes the senate should "figure out some way for us to send the appropriate message to Saudi Arabia that appropriately displays American values and American national interests".

He said the crown prince "owns this death. He owns it".

Senate majority leader Mitch McConnell, a Republican senator from Kentucky, voted against moving ahead with the resolution but said a day earlier that "some kind of response" was needed from the US for the Saudis' role in Khashoggi's death.

On Tuesday, he said that "what obviously happened, as basically certified by the CIA, is completely abhorrent to everything the United States holds dear and stands for in the world".