Riyadh, Saudi Arabia (CNN Business) Saudi Arabia's investment conference opened on Tuesday with a dearth of big name speakers and a fleeting appearance by its sponsor, Crown Prince Mohammed bin Salman.

Dozens of top business leaders from around the world had pulled out of the Future Investment Initiative as questions mounted over the Saudi government's role in the killing of journalist Jamal Khashoggi , who disappeared after entering the Saudi consulate in Istanbul.

Speaking to CNN Business at the conference, the head of Saudi oil company Aramco, Amin Nasser, said "everyone here feels sorry" about Khashoggi's death but the kingdom was pushing ahead with its investment plans. He said $50 billion worth of deals were signed on the first day of the event, which runs through Thursday.

JUST WATCHED Saudi Aramco CEO on Khashoggi's death Replay More Videos ... MUST WATCH Saudi Aramco CEO on Khashoggi's death 01:27

"We feel sorry for his family and what happened, but at the end of day you know, we need to move beyond that," Nasser told CNN Business' Emerging Markets Editor John Defterios.

"A lot of our partners are here. The ones we are doing business with are here," Nasser said.