Saudi Arabia has sought to draw a line under one of its biggest crises triggered by critic Jamal Khashoggi's murder, but an ever greater threat of international scrutiny and pressure hangs over the kingdom.Riyadh on Thursday exonerated powerful Crown Prince Mohammed bin Salman of involvement in the murder as it called for the death penalty against five men, and as the United States, a key ally, slapped sanctions on 17 suspects.The kingdom has repeatedly changed its official narrative about journalist Khashoggi's murder inside its Istanbul consulate on October 2, first denying any knowledge of his whereabouts and later saying he was killed when an argument degenerated into a fistfight.In the latest version presented by the Saudi prosecutor on Thursday, a 15-member squad was formed to bring Khashoggi back from Istanbul "by means of persuasion", but instead ended up killing The Washington Post columnist and dismembering his body in a "rogue" operation.Just hours later, the US Treasury slapped sanctions on 17 people, including close aides of Prince Mohammed, suggesting a coordinated effort between Riyadh and Washington to pre-empt the threat of harsher actions from an outraged US Congress."The (Saudi) government is accelerating its investigation and prosecution of suspects in the Khashoggi affair to defuse any potential escalation from Turkey and the US Congress," said consultancy firm Eurasia Group.The regime is still in "crisis mode", it added.The Saudi prosecutor said the operation was ordered by the deputy chief of intelligence Ahmed al-Assiri, who was advised by the royal court's Saud al-Qahtani. Both were part of Prince Mohammed's inner circle and have been sacked."Although the investigation is not particularly independent, it distanced the crown prince from the entire affair," Eurasia Group said."Yet... the affair will continue to pose challenges for the Saudi leadership."'Cover up'The Washington Post editorial board on Friday slammed the apparent contradictions in the Saudi narrative, accusing US President Donald Trump's administration of abetting a "Saudi cover up"."Congress should... suspend all military sales and cooperation with Saudi Arabia until a credible international investigation of the Khashoggi killing is completed," it said.Saudi Arabia has rejected calls for an international investigation."It currently seems like the US pressure will not go away any time soon," said Steffen Hertog, an associate professor at the London School of Economics."That said, other than sanctions on weapons deals - which Trump will resist - it is not quite clear what Congress can do. Direct sanctions against Prince Mohammed... seem unlikely, as do financial sanctions."But Saudi attempts to punish loyalist officials who were active in the operation could potentially backfire, experts say."It is very risky for the prince to threaten capital punishment to those who appeared to be following orders," said Bessma Momani, a professor at Canada's University of Waterloo."It can potentially create rogue elements within the intelligence service."Assiri - lionised in Saudi military ranks as a war hero - was not named among the 17 Saudis sanctioned by the US, but he appears sidelined.In the aftermath of the crisis, King Salman ordered a restructuring of the intelligence apparatus to be led by Prince Mohammed, who has effectively neutered his political rivals and tightened his grip on military and security agencies.Shoring up loyalty Turkey's President Recep Tayyip Erdogan has said the orders for the killing came from "the highest levels of the Saudi government", apparently alluding to Prince Mohammed. Ankara has said the kingdom's latest explanation was "insufficient".Seeking to keep up the pressure, Turkish media on Friday reported that Ankara had more evidence contradicting the Saudi version of Khashoggi's murder, including a second audio recording."The Saudis think they can run the clock on the affair and it will soon leave the spotlight," said Momani."The audio tapes are the last leverage that the Turks have and in the past few days they've made it clear they are sharing it widely."The Turkish position going forward will likely depend on "what it gets in return" for silence, she added.The US State Department said ON Thursday it was studying Turkish demands for the extradition of preacher Fethullah Gulen, who is accused by Ankara of orchestrating a failed 2016 coup.But it rejected media reports that it was meant to reduce Turkish pressure on Saudi Arabia.At home, senior Saudi royals seem to be projecting a united front to defend the kingdom.King Salman and his son, Prince Mohammed, have launched an unprecedented domestic tour to leverage their links with different tribes and religious leaders and shore up support for the leadership.At Friday sermons in big cities such as Jeddah, prayer leaders in recent weeks have defended the rulers and pushed for unwavering "loyalty", according to multiple residents.But the crisis appears to have dented the prince's absolute control on power."The era of consensus-based decision-making among senior royals is over, but Mohammad bin Salman will still have to cede some of the powers he has accumulated over the past few years," Eurasia Group said."His father has already become more involved in decisions... (and) members of the ruling family are also likely to demand greater say in consultations."