Speaking during his Justice and Development (AK) Party's group meeting at parliament, Erdogan addressed details over Turkey's investigation into the murder of Khashoggi.
"Murder of Saudi journalist Jamal Khashoggi was premeditated", Erdogan said, adding that Turkey has strong evidence that the murder was planned.
Erdogan added that all information, evidence that has been revealed till now showed that Khashoggi was the victim of a brutal murder.
Erdogan stated that it was certain that Khashoggi did not leave Saudi Consulate in Istanbul and Saudi teams made explorations in the city's Belgrad Forest and the northwestern province of Yalova before murdering Khashoggi.
In his speech, Erdogan also said that the Saudi government formally admitted to the killing of Khashoggi 17 days after his murder.
"Vienna convention would not allow such a "brutal" murder to happen", Erdogan also stated.
"Diplomatic immunity, which is a part of the Vienna Convention, will be debated", he remarked.
Separately, Erdogan offered condolences to the family and relatives of Khashoggi.
Khashoggi, a columnist for The Washington Post, had gone missing since entering the Saudi Consulate in Istanbul on Oct. 2.
After denying knowledge of Khashoggi's whereabouts for two weeks, Saudi Arabia on Saturday said he was killed during a fight inside its Istanbul consulate.
His body has not been recovered, nor has Saudi Arabia explained its shifting narrative on what transpired.
On the day of Khashoggi’s disappearance, 15 other Saudis, including several officials, arrived in Istanbul on two planes and visited the consulate while he was still inside, according to Turkish police sources. All of the identified individuals have since left Turkey.
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