US secretary of state Mike Pompeo has met with Saudi Arabia’s King Salman over the disappearance and alleged killing of Saudi writer Jamal Khashoggi, who vanished two weeks ago during a visit to the Saudi Consulate in Istanbul.

Mr Pompeo landed in Riyadh on Tuesday morning and was welcomed by Saudi foreign minister Adel al-Jubeir on landing.

Soon after, Mr Pompeo arrived at a royal palace, where King Salman greeted him.

America’s top diplomat thanked the king “for accepting my visit on behalf of President (Donald) Trump” before going into a closed-door meeting.

Saudi Arabia Missing Writer
US secretary of state Mike Pompeo, centre left, talks with Saudi Foreign Minister Adel al-Jubeir (Leah Millis/AP)

Turkish officials say they fear Mr Khashoggi was killed and dismembered inside the Istanbul consulate.

Saudi officials previously have called the allegations “baseless”, but reports in US media 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 was not immediately clear what evidence they gathered.

Mr Trump, after speaking with King Salman, had dispatched Mr Pompeo to speak to the monarch of the world’s top oil exporter over Mr Khashoggi’s disappearance.

Mr Trump himself said without offering evidence that the killing could have been carried out by “rogue killers”, offering the US-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.

Mr Pompeo also was to meet with Saudi Crown Prince Mohammed bin Salman, whom Mr 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.

Turkey Saudi Arabia Missing Writer
Security personnel inside the entrance of Saudi Arabia’s Consulate in Istanbul (Petros Giannakouris/AP)

“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 happened 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.

Turkey Saudi Arabia Missing Writer
Cleaning personnel enter Saudi Arabia’s Consulate on Monday prior to the arrival of a search team (Petros Giannakouris/AP)

According to that reported claim, the crown prince had approved an interrogation or rendition of Mr 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 been in and out of the building since Mr Khashoggi’s disappearance on October 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,” Ms Prinz said.

“Obviously, you don’t want anybody to have a chance to clean it up, but very often people do miss blood.”

Forensic officers
Mr Khashoggi disappeared two weeks ago (AP)

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 Turkey’s 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.

The Saudi consulate
Forensic officers at work in the consulate (AP)

Certain areas of the consulate were to remain off-limits, although officials would be able to inspect surveillance cameras, Turkish media reported.

What evidence Turkish officials gathered at the consulate remains unknown.

Turkey’s private DHA news agency said the Saudi consul’s office was among the rooms searched.

Mr Khashoggi has written extensively for the Post about Saudi Arabia, criticising 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 Mr 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 chief executive of Uber, a company in which Saudi Arabia has invested billions of dollars; billionaire Sir Richard Branson; JPMorgan Chase & Co chief executive Jamie Dimon; and Ford Motor executive chairman Bill Ford.

Mr Pompeo later met with Crown Prince Mohammed bin Salman.

Prince Mohammed said: “We are strong and old allies.

“We face our challenges together, the past, the day of, tomorrow.”

Mr Pompeo thanked Prince Mohammed for hosting him.