Preparations for the public listing of Saudi Arabia’s state oil company, a centerpiece of the government’s plan to open its economy, have stalled, leaving government officials and people close to the process doubting that it will go forward at all.

The initial public offering of Saudi Arabian Oil Co, better known as Aramco, was meant to be the cornerstone of the kingdom’s plan to be less reliant on oil. It would create the largest public company in the history of capital markets, an opportunity coveted by Wall Street’s biggest names.