Speaking to reporters in Ankara, Çelik said it was not possible that Saudi officials had still not found the journalist's body.
Khashoggi went missing after entering the Saudi Consulate in Istanbul on Oct. 2.
After initially saying Khashoggi had left the consulate alive, the Saudi administration admitted weeks later he had died there.
"We want to know where the body [of Khashoggi] is, we want that our authorities receive information about who the local collaborators are", Çelik said.
Reiterating that Turkey was not accusing anyone upfront, the spokesperson underscored that Ankara won't allow any cover-ups relating to the incident.
Investigation of the incident suggests a special hit squad came to the consulate to kill Khashoggi and cover up the murder. The international community refused to accept the Saudi claim that the incident was not a premeditated murder.
Turkey is seeking the extradition of 18 suspects detained in Saudi Arabia over the journalist's slaying. It also is pressing Saudi Arabia for information about who ordered Khashoggi's killing and the location of his remains.
President Recep Tayyip Erdoğan has called on Riyadh to disclose the identity of an alleged local collaborator said to have been involved in getting rid of Khashoggi's body.