DUBAI/RIYADH (Reuters) -Nadhmi al-Nasr, the long-time chief executive of the $500 billion NEOM mega-project at the heart of Saudi Arabia's drive to diversify away from oil, has departed, NEOM said on Tuesday without giving a reason.

Neom CEO Nadhmi Al-Nasr has exited the company amid allegations that workers have died and gone missing while working on the Saudi Vision 2030 project.

Following the departure of Nadhmi al-Nasr who had served as the project’s chief executive since 2018, Aiman al-Mudaifer has been appointed as interim CEO, says NEOM in a statement.

Nasr estimated the total cost of the line alone would be considerably over $2 trillion, which is far more than the country's ability to spend on development. He took the reins in 2018 and pushed staff hard.

Neom, Saudi Arabia's ambitious megacity project, is a key part of the kingdom's Vision 2030 scheme. Its CEO stepped down after six years in the role.

Neom is set to host hyper-futuristic cityscapes and structures — but financial pressures on the kingdom are changing.

Saudi Arabia announced Tuesday that it was replacing the chief executive of its futuristic mega-city NEOM as scepticism mounts over the Gulf kingdom's most ambitious development projects.

The departure of the longtime CEO marks a major shakeup at Neom, which is a showpiece of Riyadh’s economic ambitions.