The US has said the Saudi Arabian version of events surrounding Jamal Khashoggi's death has not hit the "threshold of credibility" just yet, despite Riyadh prosecuting suspects.
US officials say US Secretary of State Mike Pompeo will emphasise the need for accountability and credibility in the investigation of the Washington Post columnist's killing as he visits the Middle East – including Saudi Arabia – next week.
Briefing reporters on the trip, an official said: "The secretary has been very consistent in engagements with Saudis… to really push the two points of accountability and credibility, which is that the Saudis should have a credible narrative for what happened.
"I don't think from our point of view that the narrative emerging from the Saudis or the legal process has yet hit that threshold of credibility and accountability."
The State Department official said Mr Pompeo wanted those who carried out the killing and those who planned it to be identified by the kingdom and for those people to be punished appropriately.
Mr Khashoggi was last seen entering the Saudi consulate in Istanbul on 2 October last year.
US intelligence agencies believe Saudi Arabia's crown prince orchestrated an operation to kill the writer – a staunch critic of his – and have his body dismembered and removed to an unknown location.
Turkish authorities have also accused senior leadership of the Saudi regime over the killing.
The kingdom initially denied Mr Khashoggi was murdered but – under increasing international condemnation – later changed its story and admitted the 59-year-old was killed as part of a "rogue operation".
Saudi Arabia denies the prince ordered the killing.
Donald Trump has stood by the crown prince despite the CIA's assessment. In November, the US president said his administration planned to remain a "steadfast partner" of the kingdom.
He said: "Our intelligence agencies continue to assess all information, but it could very well be that the crown prince had knowledge of this tragic event – maybe he did and maybe he didn't!
"We may never know all of the facts surrounding the murder of Mr Jamal Khashoggi. In any case, our relationship is with the Kingdom of Saudi Arabia.
"The United States intends to remain a steadfast partner of Saudi Arabia."
Mr Trump also indicated he had no intention of cancelling $110bn (£86bn) in military contracts with Riyadh, saying: "If we foolishly cancel these contracts, Russia and China would be the enormous beneficiaries."
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He warned that oil prices would "skyrocket" too if the US made the "terrible mistake" of breaking ties with the Saudis.
Saudi state media has reported that prosecutors would seek the death penalty for at least five of 11 suspects after they attended their first court hearing.