"We have given and continue to give information and documents to anyone who is curious, although not the originals", Erdogan said of the Khashoggi file.
Erdogan has said that Turkey would reveal more evidence about the killing but was not in any rush to do so, indicating that Turkish authorities will methodically increase pressure on Saudi Arabia even as the kingdom floats conflicting statements in a vain and often clumsy attempt to end the quandary.
Al-Jubeir said 18 suspects in Khashoggi's death would be tried in Saudi Arabia, rejecting Turkey's demand for them to be extradited.
She said she had not been contacted by Saudi officials and that she was unlikely to go to Saudi Arabia for a possible funeral if Khashoggi's missing body is found.
Mattis told the forum: "We will maintain our 'twin imperatives, ' as stated by Secretary of State Pompeo, of protecting America and holding accountable those responsible for this murder".
Cengiz, a Turkish national, was placed under 24-hour police protection in Turkey on Monday, just days after Saudi Arabia finally admitted that Khashoggi had been killed inside its consulate in Istanbul. "We will subject them to a trial in court", Erdoğan said, implying that the judiciary process can take place in Turkey.
On Thursday it said evidence shows that the killing was premeditated.
In her first interview since Khashoggi's death, Hatice Cengiz, 38, told Turkish television channel HaberTurk that she continually asks herself questions about that day and the events leading up to their visit to the consulate. Saudi Arabia and the UAE have denied any involvement.
An activist, wearing a mask depicting Saudi Crown Prince Mohammed bin Salman, holds up his hands, painted with fake blood as he protests the killing of Saudi journalist Jamal Khashoggi, during a candlelight vigil outside Saudi Arabia's consulate in Istanbul, Thursday, Oct. 25, 2018.
Sunni Muslim Saudi Arabia and Shi'ite Muslim Iran, which was not represented in the Manama conference agenda, have always been locked in a proxy war, competing for regional supremacy from Iraq to Syria and Lebanon to Yemen.
Late Tuesday, the US said it would revoke the visas of 21 Saudi suspects in the Khashoggi case, and Britain followed suit on Wednesday.
Khashoggi's murder sparked global outrage and mushroomed into a crisis for the world's top oil exporting country and Prince Mohammed, the kingdom's de facto ruler.
But he said that Secretary of State Mike Pompeo had revoked the visas of Saudis suspected in the killing and that Trump had vowed "to get to the bottom of it" and get Congress involved.
The Saudi-U.S. relationship has weathered storms in the past but it is "ironclad" and much remains at stake, al-Jubeir told the Bahrain audience after Mattis' address.