Saudi Arabia's Crown Prince Mohammed bin Salman vowed on Wednesday that the killers of Jamal Khashoggi would be brought to justice, in his first public comments since the journalist's murder sparked global condemnation.

Prince Mohammed told international investors at a major conference in Riyadh that the furor over Khashoggi's killing at the Saudi consulate in Istanbul would not derail the kingdom's reform drive.

His comments came hours after US President Donald Trump was quoted by the Wall Street Journal as saying that as Saudi Arabia's de facto ruler, the crown prince bore ultimate responsibility for the operation that led to Khashoggi's death.

"We will prove to the world that the two governments (Saudi and Turkish) are cooperating to punish any criminal, any culprit and in the end justice will prevail," Mohammed said.

The world's top oil exporter has been pressured over the death of Khashoggi, a columnist and one of the crown prince's most prominent critics.

The crisis has strained Riyadh's ties with the West and led dozens of Western politicians, top world bankers and company executives to boycott the conference that opened in Riyadh on Tuesday.

French President Emmanuel Macron told King Salman in a phone call on Wednesday that Paris, in coordination with partners, could take action against those held responsible for the murder, the Elysee palace said.

Britain, also a major weapons supplier to the kingdom, described Riyadh's explanations as lacking credibility. Prime Minister Theresa May said on Wednesday that Britain would prevent all suspects in the killing from entering the country, shortly before she spoke to King Salman.

The Trump administration and the US defense industry are scrambling to save the few actual deals in a much-touted $110 billion arms package for Saudi Arabia.

The US said on Tuesday it is revoking the visas of Saudis found to be implicated in the killing of journalist Jamal Khashoggi, an event that Trump described as a "total fiasco".

"We have identified at least some of the individuals responsible, including those in the intelligence services, the Royal Court, the foreign ministry, and other Saudi ministries who we suspect to have been involved in Mr Khashoggi's death," US Secretary of State Mike Pompeo said in Washington.

"We are taking appropriate actions, which include revoking visas, entering visa lookouts, and other measures," he said on Tuesday afternoon.

Pompeo didn't provide details when prompted by the press. But the State Department later said 21 "Saudi suspects" would have visas revoked or would be declared ineligible to enter the US, The Associated Press reported on Tuesday.

The secretary of state said the move to revoke visas was just a first step.

"These penalties will not be the last word on this matter from the United States," Pompeo said. "We will continue to explore additional measures to hold those responsible accountable."

He added, however, that the US will continue to maintain a "strong partnership" with the Kingdom of Saudi Arabia.

"We continue to view as achievable the twin imperatives of protecting America and holding accountable those responsible for the killing of Mr Khashoggi," he said.

Contact the writer at huanxinzhao@chinadailyusa.com