Top Saudi intelligence officials asked a group of businessmen about using private firms to carry out assassinations at a meeting in Riyadh in March last year according to three sources 'close to the discussions', the New York Times reports.
At the time, Prince Mohammed was deputy crown prince and defense minister – suggesting top Saudi officials were considering assassinations even before he became the kingdom's de facto ruler.
The businessmen used the meeting, one of a series with Saudi officials, to pitch a $2billion plan to use private intelligence operatives in a bid to sabotage Iran's economy.
Also present at the meeting was Major General Ahmed al-Assiri, a close advisor to Prince Mohammed, who was sacked last month after the government said Khashoggi's killing was a rogue operation ordered by him.
According to the Times, General Assiri's top aides asked the businessmen about killing an enemy of Saudi Arabia - Qassin Suleimani, who is the leader of the Quds Force of Iran's Revolutionary Guards Corps.
Lebanese-American businessman George Nadar organised the meeting and Joel Zamel, an Israeli with deep ties to his nation's intelligence and security agencies, also attended.
Nadar previously met with Prince Mohammed and also pitched the Iran plan to Trump administration officials.
Both Nadar and Zamel are witnesses in special counsel Robert Mueller's investigation into the Trump campaign and have been asked about their discussions with American and Saudi officials about the Iran plan, the Times reports.
The Saudis asked whether the businessmen conducted 'kinetics' – meaning lethal operations – and said they were interested in killing senior Iranian officials.
But the businessmen said they would need to consult their lawyer, who rejected the proposal.
According to the Times, Nader told them about a company based in London that is run for former special operations troops that may be able to work with them.
They also reportedly met with Saudis, including Assiri, in a suite on one of the top floors of the Mandarin Oriental hotel in New York.
Last month, Saudi Arabia announced it had sacked al-Assiri as well as royal media advisor Saud al-Qahtani and that 18 Saudi nationals had been detained over Khashoggi's killing.
Khashoggi, a critic of Prince Mohammed, was killed at Saudi Arabia's Istanbul consulate by a team sent from Riyadh.
Saudi authorities have acknowledged that the killing was premeditated, but his body has not been found.
Saudi Foreign Minister Adel al-Jubeir said the operation was not ordered by the crown prince.
'We are determined to punish those who are responsible for this murder,' he told Fox News
'The individuals who did this, did this outside the scope of their authority. There obviously was a tremendous mistake made, and what compounded the mistake was the attempt to try to cover up.'
'We don't know, in terms of details, how. We don't know where the body is.'
But Turkish officials have accused Riyadh of carrying out a state-sponsored killing and said Khashoggi was 'strangled' and then 'dismembered' in a premeditated plan.
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