Saudi Arabian Foreign Minister Adel al-Jubeir has described the death of journalist Jamal Khashoggi as a “huge and grave mistake”, and part of a rogue operation.

Mr told al-Jubeir Fox News overnight that the “individuals who did this did this outside the scope of their authority” and would be punished.

“There obviously was a tremendous mistake made, and what compounded the mistake was the attempt to try to cover up. That is unacceptable in any government,” he said.

Saudi Arabia finally admitted that Mr Khashoggi was dead on Saturday, claiming he died following a “fist fight” at its Istanbul consulate on October 2. A Saudi official later attributed the death to a chokehold.

Both explanations have been met with widespread scepticism.

Mr al-Jubeir said that Saudi Arabia was taking action to investigate how Washington Post columnist Mr Khashoggi died and hold those responsible accountable.

“We are determined to uncover every stone. We are determined to find out all the facts. And we are determined to punish those who are responsible for this murder,” he said.

"This is a terrible mistake, this is a terrible tragedy. Our condolences go out to them. We feel their pain and I wish this didn't happen."

In an exclusive interview with @BretBaier, Saudi Foreign Minister Adel al-Jubeir delivers a message to the Khashoggi family. pic.twitter.com/upt0oRSP4g

— Fox News (@FoxNews) October 21, 2018

The statements come as US President Donald Trump said he is not satisfied with Saudi Arabia’s explanation of how Mr Khashoggi met his death in the Saudi consulate in Istanbul, but defended the Saudi royal family.

“I’m not satisfied until we find the answer,” Mr Trump told reporters Sunday night (AEST), adding that he was still considering sanctions and would speak to Crown Prince Mohammed bin Salman soon.

However, the President said it was “possible” that the crown prince knew nothing about the killing, and that cancelling an arms deal “would hurt us far more than it would them”.

Mr Trump signed arms deals worth almost $US110 billion ($155 billion) during a two-day visit to Saudi Arabia in May last year.

Three major European powers – Germany, Britain and France – released a joint statement Monday morning pressing Saudi Arabia to provide facts to back up its  explanation for the death.

Chancellor Angela Merkel said Germany would not export arms to Saudi Arabia while the current uncertainty over Mr Khashoggi’s fate persisted.

In a speech on Sunday night, Turkish president Recep Tayyip Erdogan said he was preparing to release information about the Turkish investigation the death, and would do so at his weekly speech to members of his ruling AK Party in parliament.

-with agencies