FILE PHOTO: FILE PHOTO: A demonstrator holds a poster with a picture of Saudi journalist Jamal Khashoggi outside the Saudi Arabia consulate in Istanbul, Turkey October 25, 2018. REUTERS/Osman Orsal/File Photo

ISTANBUL (Reuters) - The U.N. investigator leading the inquiry into the killing of Jamal Khashoggi said in Turkey on Thursday she had not yet received all the information she is seeking, but still hopes to conduct a successful probe.

Khashoggi, a Washington Post columnist living in the United States, was killed on Oct. 2 at the Saudi consulate in Istanbul, where he had gone to collect documents for his planned wedding.

U.S. intelligence agencies believe Saudi Arabia’s de facto Saudi ruler Crown Prince Mohammed bin Salman ordered an operation to kill Khashoggi, whose body was dismembered.

Riyadh denies the prince had any involvement.

Agnes Callamard, the U.N. special rapporteur on executions who is on a week-long mission to Turkey, has held talks in Ankara and Istanbul with government ministers, intelligence officials and Istanbul’s chief prosecutor.

“We have had good meetings here, we are still a bit disappointed that we were not able to get all the information we requested related to the investigation,” she told reporters in Istanbul.

“But we are still hopeful that the authorities will be able to deliver on their commitment and hand over to us some of the information related to police investigation,” she said, adding she hoped to conduct “a full inquiry and a successful one.”

On Tuesday, Callamard visited the consulate in Istanbul but did not go in, saying she was waiting on a request for access made to the Saudi government. She has said she could publish her report by late May, although the date could change.