Uber CEO Dara Khosrowshahi has become the latest top business leader to distance himself from the Saudi government as it faces mounting questions over its role in the disappearance of journalist Jamal Khashoggi. Khosrowshahi said in a statement late Thursday that he is withdrawing from a major business conference in the kingdom this month at which he was due to speak. “I’m very troubled by the reports to date about Jamal Khashoggi,” Khosrowshahi said in a statement late Thursday. “We are following the situation closely, and unless a substantially different set of facts emerges, I won’t be attending the FII conference in Riyadh.” His announcement is particularly significant because Saudi Arabia’s sovereign wealth fund is a big shareholder in Uber. In 2016, it invested $3.5 billion in the ride-hailing startup. The Future Investment Initiative, also known as “Davos in the desert,” is hosted by Saudi Crown Prince Mohammed bin Salman and is part of his Vision 2030 plan to break the country’s dependence on oil. Khosrowshahi was scheduled to speak about the future of transportation at the event. He joins a growing list of high-profile figures who have pulled out of the conference as concerns mount about what happened to Khashoggi, a prominent Saudi journalist, contributor to the Washington Post and critic of the Saudi regime. Khashoggi went missing last week after entering the Saudi consulate in Istanbul. Turkish officials contend he was killed inside the consulate. Saudi Arabia has denied any involvement in the disappearance of Khashoggi, saying he left the consulate the same day he went in. Richard Branson said earlier Thursday that he’s pulling back from two tourism projects in Saudi Arabia and has suspended discussions with the Saudi government about a $1 billion investment in Virgin’s space companies. “What has reportedly happened in Turkey around the disappearance of journalist Jamal Khashoggi, if proved true, would clearly change the ability of any of us in the West to do business with the Saudi Government,” the British billionaire and founder of the Virgin business empire said in a statement. Media figures pulling out Other big names who have withdrawn from the Saudi investment conference include Viacom (VIAB) CEO Bob Bakish and Ariana Huffington, the founder of the Huffington Post and an Uber board member. Huffington has also resigned from the advisory board of the conference, which is scheduled to take place between October 23 and October 25 in Riyadh. Media partners for the conference have come under particular scrutiny, and The New York Times has already pulled its partnership, saying it’s “no longer comfortable being associated with the event.” A spokesperson for CNN, which is also one of the media partners, said the network was “evaluating our participation in the conference.” Beyond the media industry, high-profile corporate partners for the event include Siemens (SIEGY) and MasterCard (MA). Siemens said it was monitoring the situation. “As of now, our plans haven’t changed and the CEO will be attending,” said Tamara Hamadan, Siemens spokesperson in the Middle East. MasterCard didn’t respond to requests for comment.