A delegation of a dozen Saudi officials was in Turkey on Saturday for talks on the disappearance of journalist Jamal Khashoggi after Riyadh slammed as “baseless lies” Turkish accusations he was killed inside its Istanbul consulate.

With the mystery of his fate unresolved 11 days after he walked into the consulate and failed to reappear, a pro-government Turkish daily said Khashoggi had recorded his own interrogation inside the mission on an Apple Watch.

Turkish officials have said they believe Khashoggi was killed inside the consulate and lurid claims have been leaked to media that he was tortured and even dismembered.

Saudi insists Khashoggi, whose writings have been critical of Prince Mohammed, had entered the consulate for paperwork for his marriage to his Turkish fiancee, left the building safely but has yet to offer visual evidence of this.

The outcry surrounding his disappearance threatens to not just harm brittle Turkey-Saudi relations but also alarm the kingdom's supporters in the West and tarnish the reform drive spearheaded by Crown Prince Mohammed bin Salman.

Top names from business and media have already cancelled plans to attend a major conference in Riyadh in October aimed at showcasing the reforms.

'Allegations and lies'

The Saudi delegation was in Turkey, due to have talks this weekend in Ankara and take part in a working group on the disappearance whose creation was announced by Erdogan's spokesman, official Turkish media said.

The NTV channel said the delegation is composed of 11 people and had on Friday inspected the consulate in Istanbul. The composition of the delegation has not been made clear.

Turkish and foreign media who have been camped outside the consulate all week noticed the motorcade arriving on Friday but it had not been immediately clear who the Saudi personnel entering the consulate were.

Read next: Istanbul outrage

Riyadh has warmly welcomed the creation of the working group but Interior Minister Prince Abdel Aziz bin Saud bin Nayef slammed the claims that Khashoggi was killed inside the consulate.

He described the allegations as “baseless allegations and lies”.

Ankara has so far trodden carefully in the controversy, with the most sensational allegations splashed in the pro-government press but President Recep Tayyip Erdogan so far stopping short of directly accusing Riyadh of wrongdoing.

Turkey and Saudi have an uneasy relationship with disputes over the ousting of the Islamist government in Egypt and blockade imposed on Ankara's ally Qatar. But Erdogan has generally been wary of needling the oil-rich conservative kingdom.

'Recorded by Apple Watch'

The latest claims reported by the pro-government Sabah daily said that Khashoggi had been wearing an Apple Watch when he entered the consulate which was synced with an iPhone left outside with his fiancee Hatice Cengiz.

It said that the watch had recorded what happened inside the consulate and this was uploaded to his cloud, although Saudis sought to partially delete it.

“The moments of Khashoggi's questioning, torture and killing were recorded on the Apple watch,” said Sabah. There was no official confirmation of the report.

The Washington Post, the US daily for whom Khashoggi is a contributor, had also reported that Turkey has sound recordings of what happened inside the consulate, including his killing and death.

Read: ‘This has not been business as usual in my country’: excerpts from Saudi journalist Khashoggi’s writings

Analysts say that Turkey is hoping to find support from its NATO ally the United States in the case, although Ankara-Washington have been in crisis over the detention for the last two years of a Protestant pastor.

But the pastor, Andrew Brunson, was freed on Friday and allowed to fly home by a Turkish court, in a move that could help normalise ties.

'Horrified' but still attending

Meanwhile Prince Mohammed's big October conference — the Future Investment Initiative dubbed by media as the “Davos in the Desert” after the annual conference in the Swiss resort — has suffered a litany of cancellations over the controversy.

Key business figures like the chief executive of ride hailing app Uber — into which Saudi's own investment fund injected money -- are no longer showing up while media groups like the New York Times, Financial Times and Bloomberg have pulled their sponsorship.

US Treasury Secretary Steven Mnuchin said Saturday that he still planned to attend, as did IMF chief Christine Lagarde.

She said she was “horrified” by the case but has to “conduct the business of the IMF in all corners in the world and with many governments.”