Saudi authorities last week claimed Khashoggi, a Washington Post contributor, was killed during a "brawl", and arrested 18 Saudis in connection with his death.
But Turkish President Recep Tayyip Erdogan earlier this week said the "savage" murder had been planned, while Turkish media have published gruesome details of Khashoggi's alleged torture and decapitation.
Turkish Foreign Minister Mevlut Cavusoglu said: "There are still questions that need answers" over the premedidated murder, demanding the Saudis explain why the 18 were arrested.
"Who gave them the orders?" he asked, pointing out that Khashoggi's body had still not been found.
"Where is (the body)? You admit they did it, but why are they not saying (where)?" Cavusoglu told a press conference in Ankara with Palestinian foreign minister Riyad al-Maliki.
"His family also wants to know and pay their final tribute." The Turkish minister repeated Erdogan's demand that those involved in the murder should be legally tried in Turkey, adding that Ankara was willing to cooperate with everyone.
Turkey did not have "any desire" to take the case to an international court, he added, but would be willing to share information and the outcomes of its investigation.
CIA Director Gina Haspel visited Ankara on Tuesday for talks, with Turkish pro-government media claiming on Wednesday intelligence officials shared evidence with her.
The officials provided Haspel with video images and audio tapes as well as evidence gathered from the consulate and the consul's residence during a briefing at the Turkish Intelligence Organisation (MIT), Sabah newspaper reported.
Asked about to confirm whether this was true, Cavusoglu said he could not provide an exact answer but said Turkey would "share documents and evidence in our hands with countries and institutions which wanted it".