The photos of him meeting with the king and the crown prince were released by the Saudi government in an apparent effort to showcase their sympathy.
How Western allies deal with Riyadh will hinge on the extent to which they believe responsibility for Khashoggi's death lies directly with the prince and the Saudi authorities.
"Even if US President Trump saves [Mohammed bin] Salman, in the eyes of the world, he is a questionable person with Khashoggi's blood on his hands", Cevik wrote.
Turkish media have also published a security camera image allegedly showing a vehicle belonging to the Saudi Consulate "scouting" a forest in the outskirts of Istanbul before Khashoggi was killed.
French President Emmanuel Macron and British Prime Minister Theresa May both spoke via telephone with King Salman, according to a statement issued by the Saudi Foreign Ministry late Thursday, hours after the European Parliament's resolution passed.
"We have maintained since the beginning that the Khashoggi murder was premeditated", a senior Turkish official told The Washington Post shortly after the Saudi announcement on Thursday.More news: No Winner Announced for Mega Millions; Jackpot is Now $1.6 Billion
"On this occasion, and from this place where the spirit of Jamal has been lost, we clearly state that we will not accept compromises in the case of his murder", the group outside the consulate said in a statement, read out in Arabic, Turkish and English. The top government lawyer in Saudi Arabia, Saud al-Mojeb, said in a statement that the team used information from Turkish officials to conclude that the killing had been planned.
"The chancellor urged Saudi Arabia to ensure a rapid, transparent and credible investigation".
Salah Khashoggi's departure came after he was photographed on Tuesday with Crown Prince Mohammed bin Salman during a condolence visit, staring coldly as the pair shook hands.
There was no immediate comment from Saudi officials, but Whitson said that they were apparently allowed to leave after a travel ban on Salah was lifted.
Dozens of people stood vigil outside the Saudi consulate in Istanbul on Thursday to demand justice.
The king assured Russian President Vladimir Putin in a phone call on Thursday that the Saudi government was determined to hold the guilty parties accountable and make sure "they receive their punishment", according to the official Saudi press agency. He was speaking at the Saudi investment conference in Riyadh dubbed "Davos in the Desert".
But striking a defiant tone, the crown prince told global investors at the three-day gathering on Wednesday that the furore would not derail the kingdom's reform drive.