(CNN) The murder of Jamal Khashoggi was "gruesome" but a United Nations report into the journalist's killing is "flawed," Saudi Arabia's Minister of State for Foreign Affairs Adel al-Jubeir said Thursday.

In an interview with CNN's Christiane Amanpour, al-Jubeir denied that Riyadh should accept responsibility for Khashoggi's murder, and said he disagreed with the findings of a UN rapporteur who laid the blame on the government.

"This is a gruesome murder that took place without authorization, for which the people who perpetrated (it) are being punished now," al-Jubeir said.

In a much-anticipated report published Wednesday, UN investigator Agnes Callamard said that there was "sufficient credible evidence" that Saudi Arabia's Crown Prince Mohammed bin Salman bears responsibility for Khashoggi's killing, and that he should be investigated for it.

Callamard said that Saudi Arabia was responsible under international law for Khashoggi's "deliberate, premeditated execution," and that current sanctions on some senior officials do not go far enough.