Turkish intelligence officials have concluded the regime critic and Washington Post columnist was dead, possibly murdered, according to international media reports.
“Australia is deeply concerned about the disappearance of Saudi journalist Jamal Khashoggi,” Ms Payne said in a statement from Papua New Guinea, where she was travelling.
“We understand the Turkish authorities are undertaking an investigation into Mr Khashoggi’s disappearance and it would be inappropriate to comment while the investigation is under way.”
The Royal Embassy of Saudi Arabia in Canberra did not respond to written questions. But on October 5 it retweeted a response from the Saudi government, containing “highlights” from an interview with the country’s day-to-day ruler, Crown Prince Mohammad bin Salman.
The Crown Prince – who has led a crackdown on foreign and domestic dissent – denied any knowledge of Mr Khashoggi’s whereabouts, insisting the journalist had left the consulate and that Saudi Arabia was “very keen” to find him.
International relations analysts told Fairfax Media it was too early to make firm conclusions on what had happened.
But Sydney University international law professor Ben Saul said Australia could expel a diplomat if Saudi intelligence were to blame for Mr Khashoggi’s death, whereas if the ruling family had a hand, Australia could enforce targeted sanctions.
“Something as serious as the assassination of a very senior, respected journalist in a foreign country’s territory is not something we should turn a blind eye to,” Professor Saul said.
Lowy Institute research fellow Rodger Shanahan said while it was possible Mr Khashoggi had died accidentally during an interrogation or an attempted abduction, Saudi Arabia’s thinking “beggars belief”.
If initial fears proved correct, Australia may have to consider scaling back co-operation with Saudi Arabia and review plans to enter into a defence industry agreement, Dr Shanahan said.
“You would have to think that would be put on the backburner, at a minimum,” he said.
Last month, Defence Minister Christopher Pyne said Australia was looking to sign formal defence industry agreements with both Saudi Arabia and its ally, the United Arab Emirates, The Australian reported.
The Herald revealed last year Australia had approved four military exports to Saudi Arabia in the previous 12 months, even as the Gulf state stood accused of war crimes in its bombardment of Yemen.
But the Australian government resisted attempts by the Senate to discover what, if any, weapons had been traded, while the Saudi embassy denied any arms had been dealt.
The financial intelligence agency AUSTRAC last month signed a memorandum of understanding with Saudi Arabia to allow for more sharing of intelligence.
“Saudi Arabia is a key partner in the global fight against terrorism and transnational crime,” an AUSTRAC spokesman said, citing “strict provisions” against releasing information that went against Australia’s policies or aims.
John Coyne of the Australian Strategic Policy Institute said Saudi Arabia was liberalising and that Australia needed to be “very cautious about interpreting what has happened on the ground” with Mr Khashoggi.
Patrick Begley is an investigative reporter for The Sydney Morning Herald.