The disappearance of Jamal Khashoggi, who has criticised Saudi Arabia for its policy in the Yemen war and its crackdown on dissent, sparked global concern after Turkish sources said authorities believe he was killed inside his nation’s consulate in Istanbul.
Saudi officials maintain he left the building unharmed.
The UK’s foreign secretary, Jeremy Hunt, said the incident would be treated seriously if reports of Mr Khashoggi’s death proved correct.
A spokesperson for the Foreign Office said: “We look forward to seeing the full results of the Turkish investigation, after which we would consider any next steps.”
Turkey’s foreign ministry said that although the Vienna Convention states consulate buildings have immunity, they can be searched by host country authorities with the consent of the mission chief.
Hami Aksoy, a spokesman for the ministry, said in a written statement that the investigation is “continuing intensively”.
His statement did not say when the premises would be searched.
The announcement came after The Washingon Post, who Mr Khashoggi wrote a column for, published a CCTV image of the journalist walking into the Saudi consulate in Istanbul just before he disappeared.
The surveillance image released by the Post bore a date-and-time stamp, accompanied by text in Turkish confirming Mr Khashoggi was arriving at the consulate.
The Post said “a person close to the investigation” shared the image with them, without elaborating.
It comes after the US called on Saudi Arabia to support an investigation into the disappearance of Mr Khashoggi.
In his administration’s first comments about Mr Khashoggi’s disappearance, Donald Trump said he was concerned by reports.
“I am concerned about it. I don’t like hearing about it. And hopefully that will sort itself out,” he said. “Right now nobody knows anything about it, but there are some pretty bad stories going around. I do not like it.”
Mike Pompeo, the US secretary of state, said: “We call on the government of Saudi Arabia to support a thorough investigation of Mr Khashoggi’s disappearance and to be transparent about the results of that investigation.”
He acknowledged the conflicting reports about the safety and whereabouts of Mr Khashoggi and said senior state officials had been in communication with Riyadh over the disappearance.
The UK was the first western government to voice concern about the US-based journalist, calling the allegations “extremely serious”.
In a statement on Monday, a Foreign Office spokesperson said: ”We are aware of the latest reports and are working urgently to establish the facts, including with the government of Saudi Arabia.”
On Tuesday, the United Nations human rights office voiced serious concern at the “apparent enforced disappearance” and called for Saudi Arabia and Turkey to investigate.
“If reports of his death and the extraordinary circumstances leading up to [it] are true, this is truly shocking,” a spokeswoman, Ravina Shamdasani, told a news briefing in Geneva.
It comes after Turkey’s president, Recep Tayyip Erdogan, publicly demanded Riyadh prove its claim Mr Khashoggi left the Saudi consulate in Istanbul.
“We have to get an outcome from this investigation as soon as possible. The consulate officials cannot save themselves by simply saying ‘he has left’,” Mr Erdogan said.
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