Saudi Crown Prince Mohammed bin Salman described slain journalist Jamal Khashoggi as a dangerous Islamist in a phone call with the White House, the Washington Post reported Thursday, quoting people familiar with the matter.

He used the characterization in the phone talk with President Donald Trump's son-in-law, Jared Kushner, and national security adviser John Bolton before the kingdom publicly acknowledged killing Khashoggi, the paper said in its online edition.

In the call, the crown prince urged Kushner and Bolton to preserve the U.S.-Saudi alliance and said the journalist was a member of the Muslim Brotherhood, a group long opposed by Bolton and other senior U.S. officials.

Saudi Arabia's public prosecutor recently said the act was carried out with premeditation, in a turnaround from earlier Saudi statements calling the Washington Post columnist's death an accident that occurred during a fistfight or interrogation.

Turkish officials have said from the beginning that Khashoggi was killed with premeditation and his body was dismembered by a team of Saudi operatives dispatched from Riyadh.

In a statement released to the Washington Post, Khashoggi's family called the characterization of the journalist as a dangerous Islamist inaccurate.

"Jamal Khashoggi was not a member of the Muslim Brotherhood. He denied such claims repeatedly over the past several years," the family was quoted as saying. "Jamal Khashoggi was not a dangerous person in any way possible. To claim otherwise would be ridiculous."