US President Donald Trump said he “is not satisfied” with Saudi Arabia’s response to the killing of Saudi journalist Jamal Khashoggi.

It follows a twist in the case in which Saudi officials confirmed Khashoggi’s death, claiming he died after getting into a fight at the Saudi consulate in Turkey on October 2.

The explanation – which comes after officials denied the journalist’s disappearance – has sparked allegations of a cover-up intended to shield powerful crown prince Mohammed bin Salman.

Trump initially said he believed the Saudi account, but has now said he still does not know where Khashoggi’s body is.

Deputy intelligence chief Ahmad al-Assiri and Saud al-Qahtani, a senior aide to the Crown Prince, have both been sacked.

Asked if he was satisfied that Saudi officials had been fired over Khashoggi’s death, he said: “No, I am not satisfied until we find the answer.

“But it was a big first step, it was a good first step. But I want to get to the answer.”

Khashoggi was last seen entering the consulate to obtain documents which would allow him to marry his fiancée, Hatice Cengiz.

At least 18 people have been arrested in connection with his death, a Saudi prosecutor said in the latest announcement.

Meanwhile, Turkish officials said they have audio evidence that the Washington Post columnist was tortured and killed by a 15-man “hit squad” flown into the country.

Some of the alleged killers have been identified as men close to the crown prince, also known as MBS.

Britain’s defence secretary Gavin Williamson was among a number of international allies calling for clarity, and said it is “very important” the Saudis give a full explanation of the circumstances of Khashoggi’s death.

High-profile figures have pulled out of a Saudi Investment summit next week billed “Davos in the desert”, including US treasury secretary Steve Mnuchin, and IMF chief Christine Lagarde.

Dutch and French finance ministers are also boycotting the three-day event.

The European Union said the emerging details of Khashoggi’s death are “deeply troubling” and said the continuing investigation should bring “proper clarity on the circumstances of the killing and ensure full accountability of all those responsible for it”.