The murder of Saudi journalist Jamal Khashoggi inside Riyadh's Istanbul consulate was "savagely planned", a spokesman for Turkey's ruling party has said.
It is the first official indication from Ankara it believes a plot was hatched in advance of the journalist's disappearance.
"This was extremely savagely planned, and we are faced with a situation where there has been a lot of effort to whitewash this," Justice and Development Party (AKP) spokesman Omer Celik told reporters in Ankara.
"This is a very complicated murder," Mr Celik said, warning that the Turkish government would not be drawn into speculation.
"Everyone (else) can speculate but we cannot speculate," he added.
He also dismissed claims of "bargaining" between Saudi Arabia and Turkey as "immoral".
Riyadh said on Saturday that Mr Khashoggi, a former regime insider turned dissident, died during a "brawl" inside the consulate after a visit on 2 October to get documents.
It added that 18 Saudis were arrested in connection with his death and two top aides of Crown Prince Mohammed bin Salman, as well as three other intelligence agents, were fired.
Before Riyadh's admission, Turkish sources said a team of 15 Saudis were sent to Istanbul and killed Mr Khashoggi, a critic of the crown prince who moved to the United States last year and wrote for the Washington Post.
Turkish pro-government media has said the team interrogated, tortured and decapitated Mr Khashoggi but a pro-government columnist Abdulkadir Selvi wrote in Hurriyet daily that Mr Khashoggi was strangled to death before he was cut up into 15 pieces.
Mr Celik pointed to CCTV footage published by CNN, which the American broadcaster claimed showed one of the Saudi officials acting as a body double for Mr Khashoggi and leaving the consulate.
A senior Turkish official quoted by CNN said that the Saudi was "brought to Istanbul to act as a body double" for Mr Khashoggi, adding: "This was a premeditated murder and the body was moved out of the consulate."
In the video a man, named by CNN as Mustafa al-Madani, left the consulate by the back exit wearing what appeared to be Mr Khashoggi's clothes - although the shoes do not match those the journalist appeared to be wearing in CCTV footage of him entering the consulate.
In a speech on Sunday, Turkish President Tayyip Erdogan appeared to suggest he was getting ready to release some information about the Turkish investigation, and would do so at his weekly speech tomorrow to members of AKP.
Turkish sources say the authorities have an audio recording purportedly documenting Mr Khashoggi's murder inside the consulate.
