Missing Saudi journalist Jamal Khashoggi may have recorded his own death on his Apple Watch, it has been claimed.

He turned on the recording function on the device before walking into the Saudi Arabia embassy in Istanbul on October 2, according to Turkish newspaper Sabah.

Then his 'interrogation, torture and killing were audio recorded and sent to both his phone and to iCloud', the newspaper report.

Jamal Khashoggi was reportedly beaten and killed on October 2 at the Saudi Arabia embassy in Istanbul, Turkey

A stock picture of an Apple Watch. Khashoggi's is said to have recorded his 'interrogation, torture and killing' in the Saudi Arabia embassy

His assailants tried to hack into the watch with multiple failed password attempts before using his fingerprint to unlock it and delete some files, the report claims.

Security forces leading the investigation into Khashoggi's disappearance found the audio file on the phone he had left with his fiancée, according to the paper.

However, unlocking an Apple Watch using fingerprint verification is not a feature of the device, an Apple representative told CNN.

It is also unclear how the file transferred from the watch to the phone.

CNN's intelligence and security analyst Robert Baer said it is highly unlikely Khashoggi could have broadcast a signal from his Apple Watch as it was too far for a Bluetooth connection.

He said: 'I think what's happened, clearly, is the Turks have the Saudi consulate wired, they have transmitters.

'The Turks don't trust any diplomats and they have been into most embassies and most consulates in Turkey and they listen to what's going on -- and if indeed there are tapes proving that he was murdered, I think that's probably how they know. But the Turks are very reluctant to admit that.'

US President Donald Trump has said Saudi Arabia could be behind Khashoggi's disappearance.

He warned that Washington would inflict 'severe punishment' if that is the case.

Trump told CBS's '60 Minutes' program during an interview on Thursday: 'We're going to get to the bottom of it and there will be severe punishment.

'As of this moment, they deny it and they deny it vehemently. Could it be them? Yes.'

The network said it will air the interview in full on Sunday evening.

CCTV of Jamal Khashoggi (wearing black suit jacket) going into the Saudi Arabia embassy in Istanbul on October 2

Conversations between those involved in Khashoggi's alleged assassination were recorded at the embassy, the Washington Post previously reported - but it was not clear how these recordings had been made or later found.

An insider told the newspaper: 'The voice recording from inside the embassy lays out what happened to Jamal after he entered.

'You can hear his voice and the voices of men speaking Arabic … You can hear how he was interrogated, tortured and then murdered.'

But Turkish officials have been reluctant to release the recording as it may give away how they spy on foreign entities based at the embassy, the newspaper reported.

The Kingdom of Saudi Arabia denies claims that something happened to Khashoggi and insist he left unharmed.

Despite there being a number of visible CCTV cameras - ringed in red - Saudi Arabia claims none of them worked on the day in question

CCTV shows Khashoggi going into the embassy and a source has told The Washington Post he was killed and then dismembered by members of security.

The US-based journalist, 59, was critical of some of Crown Prince Mohammed bin Salman's policies.

His fiancée Hatice Cengiz, 36, had been waiting outside the embassy for him but he never walked out.

Hatice Cengiz, 36, who waited outside for hours for her fiance Khashoggi to return, has spoken of being left in a 'state of deep confusion and sadness'

US Treasury Secretary Steven Mnuchin says he is 'planning' on going to a major investment conference in Saudi Arabia despite the troubling reports.

But several top CEOs and media figures have decided they will no longer attend the conference.

Billionaire mogul Richard Branson has suspended talks with Saudi Arabia over $1billion investment in Virgin Galactic.

Further evidence that Mr Khashoggi never left the consulate include screen grabs from a WhatsApp chat showing he used his phone minutes before entering the building - and then never again

TIMELINE: WHAT HAS HAPPENED IN MR KHASHOGGI'S DISAPPEARANCE OCTOBER 2 03:28: Gulf Stream IV private jet carrying suspected Saudi agents arrives at Istanbul airport. 05:05: The group checking into two hotels nearby to the Saudi consulate building. 12:13: Several diplomatic vehicles are filmed arriving at the consulate, allegedly carrying some of the Saudi agents. 13:06: Jamal Khashoggi is last seen on WhatsApp. He then hands his mobile to his fiancée Hatice Cengiz. 13:14: Khashoggi enters the consulate building. 13.24: A message is delivered to Khashoggi's WhatsApp – but it is never read. 15:08: Vehicles leave the consulate and are filmed arriving at the nearby Saudi consul's residence. 17:15: A second private jet carrying a number of suspected Saudi officials lands in Istanbul. 17:33: Khashoggi's Turkish fiancée, Hatice Cengiz, is seen on CCTV waiting outside the consulate. 18:20: One of the private jets departs from Istanbul airport. 21:00: The final plane leaves Istanbul. OCTOBER 3 The Washington Post, for whom Khashoggi writes opinion pieces, raises the alarm, saying Khashoggi has not been seen since he entered the consulate. OCTOBER 4 After an initial period of silence, Saudi Arabia says Khashoggi had disappeared 'after he left the consulate building'. *All times in Istanbul time. Advertisement

Tom Tugendhat, chairman of the Commons Foreign Affairs Committee, suggested action should be taken if the Saudi state murdered Khashoggi.

'The first thing for us to do is for us to get together with our allies, the United States, the Europeans and others, to discuss very seriously what's going on,' he told BBC Radio 4's Today programme.

'The idea that we can treat Saudi as a normal state if it practises state-sponsored murder outside its borders is simply not true.'

He added: 'We may be talking about downgrading diplomatic relations, we may be talking about restricting support for certain areas.'

He also suggested that International Trade Secretary Liam Fox could boycott a major conference in Riyadh.

'I don't think, if this is proven, that British cabinet ministers should be going, but at the moment it isn't proven so we need to be slightly cautious,' he said.

Riyadh faces a chorus of international calls to shed light on what happened to the Washington Post columnist, and business leaders have already shunned the regime.