Pompeo landed in Riyadh on Tuesday morning and was to immediately meet the king over the crisis surrounding Khashoggi. He made no remarks on landing.
Turkish officials say they fear Khashoggi was killed and dismembered inside the consulate. Saudi officials previously have called the allegations "baseless," but reports in U.S. media on Tuesday suggested the kingdom may acknowledge the writer was killed there.
Meanwhile, a Turkish forensics team finished earlier in the morning a search inside the consulate. Technicians in coveralls, gloves and covered shoes treated the diplomatic mission as a crime scene during their hours-long search. It wasn't immediately clear what evidence they gathered.
President Donald Trump, after speaking with King Salman, had dispatched Pompeo to speak to the monarch of the world's top oil exporter over Khashoggi's disappearance. Trump himself said without offering evidence that the slaying could have been carried out by "rogue killers," offering the U.S.-allied kingdom a possible path out of a global diplomatic firestorm.
However, left unsaid was the fact that any decision in the ultraconservative kingdom rests solely with the ruling Al Saud family. Noticeably absent from discussions was Saudi Crown Prince Mohammed bin Salman, whom Khashoggi wrote critically about for The Washington Post and whose rise to power prompted the writer to go into a self-imposed exile in the United States.
"The effort behind the scenes is focused on avoiding a diplomatic crisis between the two countries and has succeeded in finding a pathway to deescalate tensions," said Ayham Kamel, the head of the Eurasia Group's Mideast and North African practice. "Riyadh will have to provide some explanation of the journalist's disappearance, but in a manner that distances the leadership from any claim that a decision was made at senior levels to assassinate the prominent journalist."
CNN reported that the Saudis were going to admit the killing had occurred but deny the king or crown prince had ordered it — which does not match what analysts and experts know about the kingdom's inner workings.
The New York Times reported that the Saudi royal court would suggest that an official within the kingdom's intelligence services — a friend of Prince Mohammed — had carried out the killing. According to that reported claim, the crown prince had approved an interrogation or rendition of Khashoggi back to Saudi Arabia, but the intelligence official was tragically incompetent as he eagerly sought to prove himself. Both reports cited anonymous people said to be familiar with the Saudi plans.
Saudi officials have not answered repeated requests for comment over recent days from The Associated Press.
What evidence Turkish officials could gather at the consulate remained unknown. Saudi officials have been in and out of the building since Khashoggi's disappearance Oct. 2 without being stopped. Under the Vienna Convention, diplomatic posts are technically foreign soil that must be protected and respected by host countries.
Forensics tests like spraying luminol, a chemical mixture, can expose blood left behind, said Mechthild Prinz, an associate professor at the John Jay College of Criminal Justice who previously worked at the New York City's Office of the Chief Medical Examiner.
"It depends on how well they cleaned it up," Prinz told the AP. "Obviously, you don't want anybody to have a chance to clean it up, but very often people do miss blood."
Told that a cleaning crew walked into the consulate before the team arrived, she said: "You saw that? Wow. That's going to be a problem."
Turkey has wanted to search the consulate for days. Permission apparently came after a late Sunday night call between King Salman and Turkish President Recep Tayyip Erdogan. In statements after the call, both praised the creation of a joint Saudi-Turkish probe.
The Turkish inspection team included a prosecutor, a deputy prosecutor, anti-terror police and forensic experts, the state-run Anadolu news agency reported. Certain areas of the consulate were to remain off-limits, although officials would be able to inspect surveillance cameras, Turkish media reported.
Khashoggi has written extensively for the Post about Saudi Arabia, criticizing its war in Yemen, its recent diplomatic spat with Canada and its arrest of women's rights activists after the lifting of a driving ban for women. Those policies are all seen as initiatives of Prince Mohammed, the son of King Salman, who is next in line to the throne.
Prince Mohammed has aggressively pitched the kingdom as a destination for foreign investment. But Khashoggi's disappearance has led several business leaders and media outlets to back out of the upcoming investment conference in Riyadh, called the Future Investment Initiative.
They include the CEO of Uber, a company in which Saudi Arabia has invested billions of dollars; billionaire Richard Branson; JPMorgan Chase & Co. Chief Executive Jamie Dimon; and Ford Motor Co. Executive Chairman Bill Ford.
Trump previously warned of "severe punishment" for the kingdom if it was found to be involved in Khashoggi's disappearance, which has spooked investors in Saudi Arabia and SoftBank, a Japanese firm that manages tens of billions of dollars for the kingdom.
Trump's warning drew an angry response Sunday from Saudi Arabia and its state-linked media, including a suggestion that Riyadh could wield its oil production as a weapon. The U.S. president has been after King Salman and OPEC to boost production for weeks to drive down high crude oil prices, caused in part by the coming re-imposition of oil sanctions on Iran after the U.S. withdrawal from that's country's nuclear deal with world powers.