Robots may outnumber humans in a new pioneering city billed by Saudi Arabia as "a new blueprint for sustainable life", which would be entirely powered by renewable energy, and served by driverless vehicles and vertical farms.

The city called NEOM is to span an area of 26,500 square kilometres, stretching across the borders of northwest Saudi Arabia into Jordan and Egypt. It is designed to operate as an independent economic trade zone with its own laws, and is to become the first private business zone to span three countries.

Saudi Arabia will pump $500 billion (£382 billion) from its sovereign wealth fund, the Public Investment Fund, into nine key investment sectors in the city: energy and water, mobility, biotech, food, technological and digital sciences, advanced manufacturing, media, and entertainment.