Transcript for US has a secret recording of the murder of Washington Post columnist, Trump says

New developments in the murder of Jamal khashoggi. With the president now acknowledging he's been briefed on the audio recording of the writer's final moments. The tape concerned after the CIA concluded Saudi Arabia's crown prince ordered the killing. Tonight, the major question -- will the president take action against the key ally who denies having any role in the death? Here's Ian Pannell with more. Reporter: Tonight, the president for the first time admitting the U.S. Has a secret recording of the murder of "Washington post" writer Jamal khashoggi, killed shortly after walking inside the Saudi consulate in is Stan bull. But that he refuses to listen to it. We have the tape. I don't want to hear the tape. Why don't you want to hear it, sir? Because it's a suffering tape, it's a terrible tape. I've been fully briefed on it. There's no reason for me to hear it. Reporter: Khashoggi was a U.S. Resident, but as a Saudi citizen, he was one of the most prominent critics of the ruling royal family and the crown prince Mohammed bin Salman. Intelligence sources telling "The Washington post" the CIA has concluded it was the crown prince who ordered the assassination, but trump calling that premature. Did mbs lie to you, sir? I don't, I don't know. You know, who can really know? But I can say this, he's got many people now that say he had no knowledge. Reporter: The Saudis have vehemently denied the murder was ordered by bin Salman instead calling it a rogue operation. The Saudi ambassador to the U.S., who is the crown prince's brother, in a statement calling the claims in the purported CIA assessment false. But members of congress from both parties now speaking out saying they also believe the crown prince was behind the murder plot. He's irrational. He's unhinged. And I think he's done a lot of damage to the relationship between the United States and Saudi Arabia. Reporter: Tom, there's now growing pressure all-round on the trump administration to respond to growing allegations about the crown prince's role, saying there will be a new assessment on Tuesday. Pressure, too, on Turkey to publically release those tapes, but above all on Saudi Arabia to provide a credible explanation about who really ordered the murder of Jamal khashoggi. Tom? Ian Pannell for us tonight. Ian, thank you.

This transcript has been automatically generated and may not be 100% accurate.