US senators, bent on punishing the Saudi crown prince, Mohammed bin Salman, for the killing of journalist Jamal Khashoggi, said on Thursday they want to vote next week to penalize Riyadh, but struggled to agree on how best to do so.

Despite Donald Trump’s desire to maintain close ties to Saudi Arabia, several of his fellow Republicans have joined Democrats in blaming the crown prince for Khashoggi’s death and backing legislation to respond by ending US support for the Saudi-led war effort in Yemen, imposing new sanctions and stopping weapons sales.

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But others strongly oppose linking the Yemen conflict with the killing of the journalist.

“It would be a mistake to fracture that relationship with the Saudis. It’s not based on friendship as much as it’s based on common interests, combating extremism in the Middle East and countering the Iranian threat,” said Senator John Cornyn, the chamber’s No 2 Republican.

Five Republican and Democratic senators met behind closed doors on Thursday morning to discuss how to move ahead, saying afterward they had not yet come up with a compromise that could win enough bipartisan support to pass the Senate.

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The lack of agreement contrasted with some senators’ harsh words on Tuesday against the crown prince, the de facto ruler of the kingdom who has denied knowledge of the operation that killed Khashoggi on 2 October in the Saudi consulate in Istanbul.

A briefing by the CIA director, Gina Haspel, for senators on Tuesday hardened their resolve to act against Prince Mohammed, who has the support of Trump.

Three different measures are making their way through the Senate: a war powers resolution ending any US involvement in the Yemen conflict; legislation imposing a broad clampdown on Saudi Arabia, including ending arms sales and levying new sanctions; and a non-binding resolution targeting the crown prince.

The Senate is expected to vote on the war powers resolution next week, but lawmakers have not yet agreed on how, or whether, it should be amended. Some have questioned whether the resolution is even legal, and others said they want a response to Khashoggi’s death but agree with the Trump administration that Washington should continue to back the Saudis as an essential counterweight to Iran.

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Saudi Arabia is leading a campaign in Yemen against the Houthis, Shia Muslim fighters that Yemen’s neighbors view as agents of Iran. The war has killed more than 10,000 people and created the world’s most urgent humanitarian crisis.

Fourteen Republicans, who hold a slim majority in the Senate and rarely break from the president, have defied Trump and voted with Democrats in favor of moving ahead with the war powers resolution.

But to become law, the resolution would not just have to pass the Senate this month, but must also pass the House of Representatives and be signed by Trump, neither of which is expected this year. However, backers said Senate passage alone would still be an important step.

“A vote on the resolution is a very tough message to Saudi Arabia that the relationship is changing. And you can interpret that as a message on the Yemen war, but you can also interpret that as a message on Khashoggi,” the Democratic senator Chris Murphy, a co-sponsor, told reporters.

It was not immediately clear whether the broader legislation would come up for a Senate vote before lawmakers go home for the year and a new Congress is seated in January, or whether some provisions might be added to the war powers measure.