Saudi Arabia's explanation of the death of journalist Jamal Khashoggi is a "good first step but not enough," the US Treasury Secretary said on Sunday.

On Friday, Saudia Arabian officials said the former Washington Post columnist had died as the result of an altercation at the Saudi Consulate in Turkey.

Officials previously said Khashoggi left the consulate soon after he arrived, calling accusations he'd been killed there "baseless."

Khashoggi was last seen at the consulate in Istanbul on October 2.

JERUSALEM/RIYADH (Reuters) - Saudi Arabia's explanation of the killing of journalist Jamal Khashoggi was a "good first step but not enough," the US Treasury secretary said on Sunday, adding it was premature to discuss sanctions against Riyadh over the incident.

The comments from Steven Mnuchin are the latest from the administration of US President Donald Trump that appear aimed at censuring a killing that has sparked global outrage while protecting relations with the world's top oil exporter.

European governments have been more forceful in dismissing Riyadh's explanation that Khashoggi died following a fistfight in the Saudi consulate in Istanbul on Oct. 2. On Sunday, Britain's Brexit minister said the account was not credible.

"It would be premature to comment on sanctions and premature to comment on really any issues until we get further down the investigation and get to the bottom of what occurred," Mnuchin told reporters in Jerusalem.

He confirmed he would not attend a Saudi investment conference on Tuesday. However, he said he would visit Riyadh as planned for talks with his counterpart there on joint efforts to counter terrorist financing and plans by Washington to reimpose sanctions against Iran in November.

After denying any involvement in the disappearance of Khashoggi, 59, for two weeks, Saudi Arabia on Saturday said the journalist and critic of Crown Prince Mohammed bin Salman had died in a fistfight at the consulate. An hour later, another Saudi official attributed the death to a chokehold.

Reflecting the intensifying international skepticism over its account, a senior Saudi government official has laid out a new version that in key respects contradicts previous explanations.

Khashoggi was a critic of Saudi Crown Prince Mohammed bin Salman. Associated Press/Virginia Mayo

The latest account includes details on how the team of 15 Saudi nationals sent to confront Khashoggi had threatened him with being drugged and kidnapped and then killed him in a chokehold when he resisted. A member of the team then dressed in Khashoggi's clothes to make it appear as if he had left the consulate.

Turkish officials suspect Khashoggi, a Saudi national and US resident, was killed inside the consulate by a team of Saudi agents and his body cut up.

Trump's comments about the Khashoggi incident in recent days have ranged from threatening Saudi Arabia with "very severe" consequences and warning of economic sanctions, to more conciliatory remarks in which he has played up the country's role as a U.S. ally against Iran and Islamist militants, as well as a major purchaser of U.S. arms.

"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," Trump told reporters this weekend, when asked about the Saudi investigation and the subsequent firing of Saudi officials over the incident.

In an interview with the Washington Post, Trump said that "obviously there's been deception, and there's been lies."

A shifting narrative

Surveillance footage published by Turkish newspaper Hurriyet purports to show Jamal Khashoggi entering the Saudi consulate in Istanbul on October 2. CCTV/Hurriyet via AP

Saudi Arabia's account of the incident has changed multiple times. The authorities initially dismissed reports that Khashoggi had gone missing inside the consulate as false and said he had left the building soon after entering. When the media reported a few days later that he had been killed there, they called the accusations "baseless."

Britain's Brexit minister, Dominic Raab, said the explanation that Khashoggi had died after a fistfight was not believable.

"No, I don't think it is credible," he said in an interview on BBC TV.

For Western allies, a main question will be whether they believe that the prince, who has painted himself as a reformer, has any culpability. King Salman, 82, had handed the day-to-day running of Saudi Arabia to him.

Trump has forged close ties with Saudi Arabia and the crown prince, citing the kingdom's economic importance and its role in countering the influence of rival Iran in the region.

French Finance Minister Bruno Le Maire said Saudi Arabia's admission that Khashoggi had been killed was welcome "progress," but urged the kingdom to follow through with a full and transparent investigation.

"I note that the Saudi authorities have changed tack, admitted the facts and accepted some responsibility, so we're making progress," Le Maire said on France 3 television. "But full light needs to be shed."

Some governments and prominent executives have said they would pull out of an upcoming investment conference in Saudi Arabia. Among the latest, the government of New Zealand said it would not attend, as did the head of the main banking unit of Japanese financial group MUFG.

The search for Khashoggi's body

Khashoggi, a prominent Saudi journalist, has been missing since October 2. Reuters

According to the senior Saudi official, the Saudi team rolled up Khashoggi's body in a rug, took it out in a consular vehicle and handed it to a "local cooperator" for disposal.

One of the operatives then donned Khashoggi's clothes, eyeglasses and Apple watch and left through the back door of the consulate to make it look like Khashoggi had walked out of the building, the senior Saudi official said.

Turkish investigators are likely to find out what happened to the corpse "before long", a senior Turkish official said on Saturday.

Officials told Reuters in Turkey on Thursday that Khashoggi's remains may have been dumped in Belgrad Forest adjacent to Istanbul, and at a rural location near the city of Yalova, 90 km (55 miles) south of Istanbul.

Turkish sources say the authorities have an audio recording purportedly documenting Khashoggi's murder inside the consulate.

Pro-government Turkish newspaper Yeni Safak, citing the audio, said his torturers cut off his fingers during an interrogation and later beheaded him.

Trump said no one from his administration had seen video or a transcript of what happened inside the consulate.

Additional reporting by Kylie MacLellan in London, Laurence Frost in Paris, Taiga Uranaka in Tokyo and Praveen Menon in Wellington; Writing by David Dolan; Editing by Dale Hudson.