Defense Secretary Jim Mattis condemned the killing of Washington Post contributor and Saudi government critic Jamal Khashoggi as intolerable, minutes before Saudi Arabia's foreign minister, at the same venue, characterised the global reaction to the murder as hysterical.

Mattis suggested the killing threatened to undermine stability in the Middle East, his first substantive comments on the matter. The defense secretary made the remarks at a security conference in the island kingdom of Bahrain, across the bridge from Saudi Arabia, minutes before Saudi Foreign Minister Adel al-Jubeir took to the stage and said people were jumping to conclusions before the investigation was completed.

Mattis reiterated President Donald Trump's vow to get to the bottom of what happened to Khashoggi, who disappeared at the Saudi Consulate in Istanbul on October 2, and said Secretary of State Mike Pompeo would be taking unspecified "additional measures" in response to the killing beyond the revocation of US visas for certain Saudi suspects. Above all, Mattis characterised the matter as not only a human rights issue but also a national security concern for nations in the Middle East.

"When opposing voices can be heard within a political process adapted to each nation's culture, one that permits peaceful opposition by giving voice and human rights to all, a nation becomes more secure," Mattis said. "When people can speak and be heard calling for peace and respect for all, the terrorist message of hatred and violence is not embraced. With our collective interests in peace and unwavering respect for human rights in mind, the murder of Jamal Khashoggi in a diplomatic facility must concern us all greatly."