Saudi Crown Prince Mohammed bin Salman told the US he considered murdered journalist Jamal Khashoggi to be a dangerous Islamist, media reports say.
Prince Mohammed's reported phone call to the White House came before Saudi Arabia admitted he had been killed inside the Saudi consulate in Istanbul, according to BBC.
Saudi Arabia has denied the reports in the Washington Post and New York Times.
A Saudi national and well-known critic of Saudi rulers, Khashoggi was killed and his body dismembered on 2 October.
His remains have not yet been found.
On Friday, Yasin Aktay, an adviser to Turkey's president, told Hurriyet newspaper that Khashoggi's body "wasn't just cut up", but that the murderers "got rid of the body by dissolving it".
His fiancée, Hatice Cengiz, has called on world leaders to "bring the perpetrators to justice", in an editorial for the Guardian and other newspapers.
Saudi Arabia denies its royal family was involved and says it is "determined to find out all the facts".
Late last month, Prince Mohammed said that "the crime was painful to all Saudis".
During the call with President Donald Trump's son-in-law Jared Kushner and National Security Adviser John Bolton, Prince Mohammed said Khashoggi had been a member of the Muslim Brotherhood, a transnational Islamist organisation, the Washington Post reported.
The phone call is reported to have taken place on 9 October, a week after Khashoggi disappeared.
Prince Mohammed also reportedly urged the White House to preserve the US-Saudi alliance.
According to a New York Times report, friends of Khashoggi said he joined the Muslim Brotherhood as a young man, but later became inactive.
Following the Arab Spring uprisings in 2011, Kashoggi expressed support for Islamist groups that had gained power in several countries.
However, his family denied he was a member of the Brotherhood and said the murdered writer had himself denied this repeatedly in recent years.
"Jamal Khashoggi was not a dangerous person in any way possible. To claim otherwise would be ridiculous," his family said in a statement to the Washington Post.
