Mohammad Bin Salman has spoken about his role in Jamal Khashoggi's murder for the first time

The Saudi officials who killed journalist Jamal Khashoggi in their Istanbul consulate must reveal the location of his body, Turkey's president said as he sharply criticised the kingdom's handling of the case.

Recep Tayyip Erdogan also said Saudi Arabia's chief prosecutor will arrive in Turkey on Sunday as part of the investigation and will meet Turkish counterparts.

Turkey's state-run news agency said Turkish prosecutors plan to seek the extradition of 18 suspects.

Anadolu Agency said the Istanbul chief prosecutor's office submitted its request to the justice ministry, and the foreign ministry will formally request the extraditions.

On Thursday, Saudi prosecutors said Khashoggi's killing was premeditated, citing Turkish evidence and changing the country's account again to try to ease international outrage over the murder of a prominent critic of crown prince Mohammed bin Salman.

Turkey has other "information and evidence" about the killing by Saudi officials after Khashoggi entered the consulate on 2 October, and it will eventually reveal that information, Mr Erdogan said.

"There is no point in being too hasty," he said in an indication that Turkey is prepared to maintain pressure on Saudi Arabia, even as the kingdom struggles for ways to end the crisis.

CIA director Gina Haspel was in Turkey earlier this week to review evidence, and she briefed Donald Trump in Washington on Thursday.

What the US president called "one of the worst cover-ups in the history of cover-ups" was revealed to the world by Turkish leaks of information, including references to purported audio recordings of the killing, and security camera footage of the Saudi officials involved as they moved around Istanbul.

Key mysteries remaining include whether the killing was carried out with the knowledge of the crown prince, who denies it, and the location of Khashoggi's body.

"It is clear that he has been killed but where is it? You have to show the body," Mr Erdogan said during an address to Turkey's ruling party leaders.

He criticised initial Saudi statements that claimed Khashoggi had left the consulate unharmed after going there for paperwork related to his planned marriage to a Turkish woman.

"He will leave the consulate and not take his fiancee with him? Such childish statements do not go hand in hand with statesmanship," said Mr Erdogan, again urging Saudi Arabia to turn over 18 suspects the kingdom said it had arrested and would punish for the crime.

"If you cannot get them to speak ... then hand them over to us and let us put them on trial," he added.

Jamal Khashoggi death: key figures Show all 7 1 /7 Jamal Khashoggi death: key figures Jamal Khashoggi death: key figures Jamal Khashoggi Washington Post journalist who was critical of the Saudi regime and the young Crown Prince Mohammed bin Salman, he was murdered on 2 October in the Saudi Arabian consulate in Istanbul AFP Jamal Khashoggi death: key figures Saudi Crown Prince Mohammed bin Salman Heir to the Saudi throne, Mohammed bin Salman has been implicated in the murder, with US officials claiming that he must have known of the plot AFP/Getty Jamal Khashoggi death: key figures 15 man hit squad Turkish police suspect these 15 men of being involved in the murder of Jamal Khashoggi, issued 10 October, 8 days after the journalist disappeared EPA Jamal Khashoggi death: key figures Saud al-Qahtani Aide to Crown Prince Mohammed bin Salman, Saud al-Qahtani is claimed to have ordered Khashoggi's murder Saud Al-Qahtani/Twitter Jamal Khashoggi death: key figures Maher Abdulaziz Mutreb A former diplomat who often travelled with the Crown Prince, Mutreb was initially claimed to be the leader of the hit squad and is pictured here entering the Saudi consulate on the day of the murder AP Jamal Khashoggi death: key figures Mustafa al-Madani First implicated in the 15 CCTV photos released by the Turkish police, al-Madani was later found to have been used as a body double for Khashoggi, leaving the Saudi consulate dressed in his clothes on the day the journalist was killed CNN Jamal Khashoggi death: key figures Salah bin Jamal Khashoggi (L) Son of the murdered journalist met with Crown Prince Mohammed bin Salman on 23 October EPA

Mr Khashoggi's son Salah has left Saudi Arabia after the kingdom revoked a travel ban, allowing him to travel to the US.

Mr Khashoggi's fiancee said later that she has not received any condolence call from Saudi officials.

Hatice Cengiz, who is Turkish, also said in an interview on Turkish television channel HaberTurk: "I found myself in a darkness I cannot express."

She said she had asked US secretary of state Mike Pompeo, who called her about the case, whether he had any news that would make her happy.

"But he said he didn't," she added.

State department spokesperson Robert Palladino said Washington welcomed the decision to have Salah Khashoggi and his family leave Saudi Arabia. His US destination was not immediately known but his late father lived in the Washington area.

The statement from Saudi prosecutors that evidence showed Khashoggi's killing was premeditated contradicted an earlier Saudi assertion that rogue officials from the kingdom had killed him by mistake in a brawl.

That assertion, in turn, backtracked from an initial statement that Saudi authorities knew nothing about what happened to the columnist for the Washington Post.

The shifting explanations indicate Saudi Arabia is scrambling for a way out of the crisis that has enveloped the world's largest oil exporter and a major US ally in the Middle East.

But a solution seems a long way off, partly because of deepening scepticism in Turkey and elsewhere that the brazen crime could have been carried out without the involvement of Prince Mohammed, the kingdom's heir apparent.

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