Germany joined France and the United Kingdom in a call for a "credible" investigation into the disappearance and death of Khashoggi, a prominent critic of Saudi policies, who was last seen entering Saudi consulate on October 2. A member of the team dressed in Khashoggi's clothes to make it appear as if he had left the consulate.
Reuters reported on Sunday it had spoken to a Saudi official who said Mr Khashoggi had died in a chokehold after resisting attempts to return him to Saudi Arabia.
"We have to see if financial motives are influencing the president", he said on ABC.
On Sunday, the Saudis claimed the initial plan was to kidnap Khashoggi and try and persuade him to return to Saudi Arabia but to release him unharmed if he refused.
The Turkish leader's statement came the day after Saudi authorities conceded Khashoggi had been killed inside their diplomatic compound in Istanbul.
The European Union says the emerging details of Saudi journalist Jamal Khashoggi's death are "deeply troubling" and that a "continued thorough, credible and transparent investigation" is needed.
Saudi Arabia faced a growing chorus of incredulity on Sunday, with world powers including Britain and France demanding answers and some American politicians calling for tough, concerted action to punish the Saudi royal family if it were proven to be responsible. But in an interview with The Post late Saturday, Trump conceded that there had been "deception".
Mr Trump has cited a planned US$110 billion arms sale to Saudi Arabia as a reason for a cautious approach, although many components of that package had been set in motion months or years before he took office. Both areas are now being searched for Khashoggi's remains.
President Trump initially said the Saudi explanation of Khashoggi's death was credible.
The crown prince has denied any involvement. Central Intelligence Agency officials have listened to the audio recording that Turkey says proves Khashoggi was killed by Saudi agents in the consulate, according to people briefed on the matter.
The official Saudi Press Agency (SPA) said on Sunday that the Monarch, Salman bin Abdulaziz, and his son, Mohammed bin Salman, telephoned Salah Jamal Khashoggi to express their condolences, reports Efe news.
For his part, Salah Jamal Khashoggi thanked the crown prince for his condolences.
Speaking late Saturday after a campaign rally in Nevada, he said he will be talking to Saudi Crown Prince Mohammed bin Salman soon. The president has raised the possibility of imposing sanctions but said halting an arms deal would "hurt us more than it would hurt them".