US PRESIDENT DONALD Trump has said for the first time that Saudi crown prince Mohammed bin Salman could have been involved in the killing of journalist Jamal Khashoggi, adding that “if anybody were going to be, it would be him”.

Trump told the Wall Street Journal that bin Salman was “running things over there” in the Saudi capital Riyadh, increasing international pressure over the killing.

It comes as the Saudi crown prince is to make his first international speech today since the killing of Washington Post columnist Khashoggi at the Saudi Consulate in Istanbul.

Bin Salman is to address the Future Investment Initiative summit in Riyadh this afternoon.

The summit is the prince’s brainchild, an effort to draw much-needed foreign direct investment into the kingdom to create jobs for its young population.

However, this year’s summit has been overshadowed by the 2 October killing of Khashoggi. Turkish officials say the writer was killed by a 15-man Saudi hit squad that included a member of Prince Mohammed’s entourage on overseas trips.

Saudi Arabia has suggested, without offering evidence, that the team went rogue.

Many international business leaders have pulled out of attending the summit over Khashoggi’s slaying.

‘Worst cover-up in the history of cover-ups’

Yesterday, US President Donald Trump slammed “one of the worst cover-ups in the history of cover-ups” as the US confirmed it would be revoking 21 Saudi visas in the wake of the killing.

The move came as Turkish President Recep Tayyip Erdogan said Khashoggi’s killing inside the Saudis’ Istanbul consulate had been meticulously planned, in a speech that overshadowed the long-planned investment forum in Riyadh.

Crown Prince Mohammed bin Salman “strongly said that he had nothing to do with this, this was at a lower level,” US President Donald Trump said, adding he had spoken on Monday to the prince and his father King Salman.

Trump said the Saudis had a “very bad original concept” in killing the 59-year-old Saudi insider-turned-critic.

“It was carried out poorly and the cover-up was one of the worst in the history of cover-ups,” Trump said.

“It was a total fiasco,” he later added. “I’m saying they should have never thought about it. Once they thought about it, everything else they did was bad too … It should have never happened.”

Faced with mounting calls for tough measures by US lawmakers across the political spectrum, the State Department said it had identified 21 Saudis whose visas would either be revoked or who would be ineligible for future visas.

“These penalties will not be the last word on this matter from the United States,” Secretary of State Mike Pompeo told reporters.

“We are making very clear that the United States does not tolerate this kind of action to silence Mr Khashoggi, a journalist, through violence,” he said.

The top US diplomat said the Saudi suspects came from “the intelligence services, the royal court, the foreign ministry and other Saudi ministries.”

Pompeo added the United States was also looking into whether to take action under a law named after Sergei Magnitsky, the anti-corruption accountant who died in Russian custody, that would impose financial sanctions on individuals behind Khashoggi’s death.

The initial US action against the Saudis came three weeks after Khashoggi, self-exiled to suburban Washington, vanished in the consulate and following contradictory statements by Trump, who has ruled out major steps such as cutting arms sales to the major defense partner.

With reporting from AFP