But following "reports we were getting from Turkey", Saudi authorities began an investigation, which discovered "he was killed in the consulate".
Asked if he believed the Saudi government's explanation, Mr Raab said: "No, I don't think it's credible".
Adel al-Jubeir told Fox News on Sunday that those responsible will be held accountable for "this huge and grave mistake".
The United States and saudi Arabia announce mega-contracts in excess of $ 380 billion, of which 110 are for sales of arms americans in Riyadh aimed at countering the "threats to iran and to combat the islamist radicals".
The dissident Saudi Arabian journalist Jamal Khashoggi, who was killed by Saudi security sleuth at their Consulate in Istanbul, was struggling each morning discovering fresh hell unleashed on his mobile screen, the misdeeds of the internet army assigned by Crown Prince Mohammed Bin Salman also known as MBS among his western friends. Saudi authorities said they had fired five top officials and arrested 18 other Saudi nationals as a result of the preliminary investigation. [What we know about the 15 Saudis said to have played a role in the Khashoggi case] Turkish investigators are still searching for Khashoggi's body, which they believe was cut into pieces after he was killed.
TRT World has obtained exclusive pictures which show Saudi journalist Jamal Khashoggi entering the Saudi consulate in Istanbul on October 2, hours before he was reported missing after he failed to come out of the building.
Reflecting global scepticism over its account, a senior Saudi government official laid out a new version that contradicts previous explanations.
"There were not people closely tied to him".
But that narrative - combined with the absence of Khashoggi's body - quickly drew scepticism and scorn from many, including staunch allies.
According to the plan, the team could hold Khashoggi in a safe house outside Istanbul for "a period of time" but then release him if he ultimately refused to return to Saudi Arabia, the official said.
Chancellor Angela Merkel signaled that Germany will suspend exports of military equipment to Saudi Arabia pending investigations into the death of government critic Jamal Khashoggi.
Foreign Secretary Jeremy Hunt is considering the "next steps" in Britain's response to the case, officials said.
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". McKinsey said it was investigating how and with whom the document was shared.
"Do I think he did it?" But it was a big first step, it was a good first step. "I'm not satisfied until we find the answer", he said, referring to how Khashoggi died.
Corker also sought in the interview to stress the strategic importance that Saudi Arabia would have to inform the United States response.
A growing chorus of US lawmakers including several from President Donald Trump's Republican Party have criticized the Saudi leadership over the affair, but Jubeir was confident the US-Saudi relationship would survive the crisis.
"[Such an admission] was predicted as the evidence was too strong to be denied", Manan said.