Central Intelligence Agency Director Gina Haspel will brief US Senate leaders on Tuesday morning regarding CIA's findings about the death of Khashoggi at the Saudi consulate in Istanbul on October 2, the Wall Street Journal reported on Monday.

Following last week's briefing by US Secretary of State Mike Pompeo and Defense Secretary James Mattis, many US senators requested to hear directly from the CIA chief about the killing. Both secretaries said Washington has no direct evidence proving that Saudi Arabia's Crown Prince Mohammed bin Salman was involved in Khashoggi's murder.

Last month, a CIA leak to several news outlets revealed the agency concluded with "high confidence" that Khashoggi's murder was ordered by the Saudi crown prince. However, US President Donald Trump has said that the CIA did not have any definitive answer on whether bin Salman had been aware of the Washington Post columnist's murder.

Khashoggi, who had been a journalist and a prominent critic of Saudi Arabia's government, went missing after he entered a Saudi consulate in Istanbul on October 2. After weeks of denying any knowledge about his whereabouts, Riyadh admitted that the journalist had been killed inside the consulate.

On October 26, the Saudi prosecutor general acknowledged that the journalist's murder was premeditated. However, Riyadh maintains that the killing had nothing to do with the Saudi royal family, describing it as a rogue operation.

Saudi Arabia's Foreign Minister Adel Jubeir said Khashoggi had been killed by people who criminally overstepped their authority.

US lawmakers have called for harsh measures including a suspension of arms sales to Riyadh in response to both the killing of Khashoggi and mounting civilian casualties in Yemen.