Trump says missing Saudi journalist Khashoggi likely dead, warns of 'very severe' consequences

US President Donald Trump has said it looks like Saudi Arabia's missing dissident journalist Jamal Khashoggi is dead and warned of "very severe" consequences if the kingdom is responsible.

Khashoggi, 60, who has not been seen since entering Saudi Arabia's consulate in Istanbul earlier this month, is feared to have been killed inside the mission. The incident has resulted in a global outrage, more so in the US where he lived as a legal permanent resident and worked for 'The Washington Post'.

"It certainly looks that way to me. It's very sad. Certainly, looks that way,” Trump told reporters at Joint Air Force base Andrews before boarding Air Force One on his way to Montana for a campaign rally.

This is the first time that the US has officially acknowledged about Khashoggi's death, who was last seen entering the Saudi consulate in Istanbul.

Turkish investigators have told local media and also to the US media that Khashoggi was brutally killed inside the consulate on October 2.

"Well, it'll have to be very severe. I mean, it's bad, bad stuff. But we'll see what happens," Trump told reporters when asked what would be the consequences of such an unfortunate incident.

The President's remarks came hours after he had a detailed meeting with Pompeo, who a night earlier arrived from his trip to Saudi Arabia and Turkey, where he talked to them about the missing journalist.

"We are waiting for some investigations, and waiting for the results. We will have them very soon, and I think we'll be making a statement, a very strong statement. But we're waiting for the results of about three different investigations, and we should be able to get to the bottom fairly soon," Trump said.

Trump so far has resisted the call for strong action against Saudi Arabia.

During his meeting with Trump, Pompeo advised that Saudi Arabia be given some more time to complete investigation.

"We've made clear to them that we take this matter with respect to Mr Khashoggi very seriously. They've made clear to me they, too, understand the serious nature of the disappearance of Mr Khashoggi," Pompeo said.

"They also assured me that they will conduct a complete, thorough investigation of all of the facts surrounding Mr Khashoggi, and that they will do so in a timely fashion, and that this report itself will be transparent for everyone to see, to ask questions about, and to inquire with respect to its thoroughness," he said.

"And I told President Trump this morning that we ought to give them a few more days to complete that, so that we, too, have a complete understanding of the facts surrounding that. At which point we can make decisions about how or if the United States should respond to the incident surrounding Mr Khashoggi," said the top American diplomat.

Meanwhile several lawmakers led by Congressman Jim McGovern introduced a legislation in the House to prohibit all US arms sales to Saudi Arabia until Secretary of State determines that the Saudi regime is not responsible for the disappearance or death of Khashoggi.

If the Saudi government is found to be culpable in Khashoggi's disappearance, the legislation prohibits all US military aid and sales to Saudi Arabia until Congress passes a resolution approving such sales.

House Democratic Whip Steny H Hoyer said the reported death of Khashoggi at the hands of Saudi officials is appalling, as is the Trump Administration's failure to hold the government of Saudi Arabia accountable for its actions.

"Given the reports surrounding Mr Khashoggi's disappearance, America's relationship with Saudi Arabia ought to be carefully scrutinised, as should any possible sale of US weapons to Saudi Arabia," he said.

"If the President refuses to stand up to Saudi Arabia, it is incumbent upon Congress to take a stand to not only defend US values, but to send a strong signal of support to journalists and democracy activists everywhere," Hoyer added.

In a related development, the Committee to Protect Journalists, Human Rights Watch, Amnesty International, and Reporters Without Borders on Thursday urged Turkey to urgently ask UN Secretary-General Antonio Guterres to establish a UN investigation into the possible extrajudicial execution of Khashoggi.