Journalist Jamal Khashoggi repeatedly told his killers "I can't breathe" during his final moments in the Saudi consulate in Istanbul, CNN reported on Monday.

Istanbul’s chief prosecutor has filed warrants for the arrest of a top aide to Saudi Arabia’s de facto ruler and the deputy head of its foreign intelligence on suspicion of planning the killing of Jamal Khashoggi, two Turkish officials said on Wednesday.

The CIA believes Saudi Crown Prince Mohammed bin Salman ordered the killing of journalist Jamal Khashoggi in Istanbul, sources familiar with the matter said on Friday, complicating President Donald Trump’s efforts to preserve ties with a key U.S. ally.

An international investigation into the murder of Saudi journalist Jamal Khashoggi is essential, Turkey’s foreign minister said on Wednesday, and reiterated Turkish decisiveness to solve the murder.

Canadian intelligence officers have listened to Turkish recordings of what happened to Saudi journalist Jamal Khashoggi, Prime Minister Justin Trudeau said on Monday, adding that he was discussing with allies what next steps should be taken.

Turkey has given recordings related to the killing of Jamal Khashoggi to Germany, France and Britain, President Tayyip Erdogan said on Saturday, seeking to maintain international pressure on Riyadh over the Saudi journalist’s death.

Turkey has been granted a waiver of around 25 percent on U.S. oil sanctions against Iran, Turkish Energy Minister Fatih Donmez said on Friday, amounting to around three million tonnes of oil annually.

Qatar’s Emir Sheikh Tamim bin Hamad al-Thani will meet with Turkish President Tayyip Erdogan on Friday during a visit to Turkey, the Turkish presidency said on Thursday.

The order to kill journalist Jamal Khashoggi came from the “highest levels” of the Saudi government, Turkish President Tayyip Erdogan said in the Washington Post on Friday and he called for the “puppetmasters” to be unmasked.

The United States said on Friday it will temporarily allow eight importers to keep buying Iranian oil when it re-imposes sanctions on Monday to try to force Iran to curb its nuclear, missile and regional activities.

Istanbul’s chief prosecutor’s office said on Wednesday that journalist Jamal Khashoggi was suffocated in a premeditated killing as soon as he entered Saudi Arabia’s consulate four weeks ago, and his body was then dismembered and disposed of.

The Turkish lawyer looking into the death of Jamal Khashoggi has asked Saudi Arabia’s prosecutor to disclose who sent the team involved in the journalist’s killing, President Tayyip Erdogan said on Tuesday.

Turkish prosecutors have prepared an extradition request for 18 suspects from Saudi Arabia in the killing of journalist Jamal Khashoggi, authorities said.

He ran social media for Saudi Arabia’s crown prince. He masterminded the arrest of hundreds of his country’s elite. He detained a Lebanese prime minister. And, according to two intelligence sources, he ran journalist Jamal Khashoggi’s brutal killing at the Saudi consulate in Istanbul by giving orders over Skype.

Britain said questions remained over the killing of journalist Jamal Khashoggi, and only Saudi Arabia could provide answers to them.

President Donald Trump said Saudi authorities staged the “worst cover-up ever” in the killing of prominent journalist Jamal Khashoggi this month, as the United States vowed to revoke the visas of some of those believed to be responsible.

“Intelligence and security institutions have evidence showing the murder was planned,” Erdogan told members of his AK Party in parliament.

Five Turkish employees of the Saudi consulate in Istanbul are giving statements as witnesses under an investigation into the killing of Saudi journalist Jamal Khashoggi, Turkish broadcaster NTV said on Monday.

Turkish authorities were prevented from searching a parked Saudi diplomatic car in Istanbul on Monday because they were not given permission from the consulate, private broadcaster NTV said.

US President Donald Trump said on Saturday that he is not satisfied with Saudi Arabia’s explanation for the circumstances around the killing of journalist.