In her long anticipated report , which was released on Wednesday, UN extrajudicial executions investigator Agnes Callamard said Khashoggi’s death “constituted an extrajudicial killing for which the State of the Kingdom of Saudi Arabia is responsible”.

Khashoggi’s killing by a team of Saudi operatives in the Saudi consulate in Istanbul on October 2 provoked widespread revulsion and marred the image of the crown prince.

The report cites audio from inside the consulate, recorded just minutes before Khashoggi entered.

In the audio, Maher Abdulaziz Mutreb, a close aide to bin Salman, asked whether it will “be possible to put the trunk in a bag?”

In response, Salah Mohammed Abdah Tubaigy, a well-known Saudi forensics doctor, replied “No. Too heavy,” after which he expressed hope that Khashoggi’s killing would “be easy”.

“Joints will be separated. It is not a problem. The body is heavy. First time I cut on the ground. If we take plastic bags and cut it into pieces, it will be finished. We will wrap each of them,” Tubaigy said in the recording, adding: “Leather bags”.

There was a reference to cutting skin, according to the report.

Tubaigny also expressed concerns that his direct manager was not aware of what he was doing. “There is nobody to protect me.” At the end of the conversation, Mutreb asked whether “the sacrificial animal” has arrived.

At 13:13 local Istanbul time, a voice said “he has arrived”, the report said. In these recordings heard by the special rapporteur, Khashoggi’s name was not mentioned.

Callamard said she “determined that there is credible evidence, warranting further investigation of high-level Saudi Officials’ individual liability, including the crown prince’s.” Saudi cover story

Al Jazeera’s diplomatic editor James Bays, reporting from the UN headquarters in New York, described the findings as “damning”.

“It’s a report that is pretty certain of who is to blame – she (Callamard) says Saudi Arabia is responsible for premeditated murder,” Bays said.

“It completely blows away the official Saudi cover story that this was a botched plan to seize Khashoggi and take him back to Saudi Arabia,” he added.

There was no immediate reaction from Riyadh which was sent the 100-page report in advance.

Al Jazeera’s Hashem Ahelbarra, reporting from outside of the Saudi consulate in Istanbul where Khashoggi was killed, said the report’s findings were likely to provide Turkey with “momentum” to put pressure on US President Donald Trump to “come out and take action against bin Salman”.

The report also said that Saudi Arabia must apologise to Turkey for “abuse of diplomatic privileges”.

Callamard in her report confirmed earlier findings after a visit to Turkey this year that the evidence pointed to a brutal crime ” planned and perpetrated ” by Saudi officials.

Khashoggi’s remains have not been found but Callamard has said that she and her team of forensic and legal experts had access to a part of “chilling and gruesome audio materials” of his death obtained by the Turkish intelligence agency.

Matthew Bryza, a former US ambassador and a non-resident senior fellow at the US-based Atlantic Council think-tank, said the findings made clear Khashoggi’s killing was “a premeditated murder, planned carefully”.

“The Saudi government must come up with an explanation for who ordered this, who’s responsible and where is the body,” Bryza told Al Jazeera from Istanbul.

“This report builds and restores momentum for justice to be done.”

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The CIA and some Western countries reportedly believe bin Salman , also known as MBS, ordered the operation to kill Khashoggi, a critic of the crown prince’s policies and Washington Post columnist.

Saudi officials have denied these suspicions.

Callamard had earlier denounced the lack of transparency at the kingdom’s secretive hearings for 11 suspects accused in the murder.

She called on Saudi authorities to reveal the defendants’ names, the charges against them and the fate of 10 others initially arrested.

US President Donald Trump’s administration said it was pressing its close Middle East ally Saudi Arabia to show “tangible progress” towards holding to account those behind the Khashoggi killing.

Washington wants the Saudis to do so before the one-year anniversary of his murder, a senior administration official said last week.

Callamard is due to present her report on June 26 to the UN Human Rights Council, whose 47 member states include Saudi Arabia.

The French national is also director of the Global Freedom of Expression initiative at Columbia University in New York. DM