By Pesha Magid, Hadeel Al Sayegh and Federico Maccioni RIYADH/DUBAI (Reuters) -Saudi Arabia has scaled back lofty ambitions for its NEOM gigaproject to prioritize completing elements essential to hosting global sporting events over the next decade as rising costs weigh,

Saudi Arabia's ambitious futuristic city plans have been bogged down by delays and changes. The most recent is the departure of its CEO, Nadhmi al-Nasr.

Crown Prince Mohammed bin Salman has poured hundreds of billions of dollars into development projects through the kingdom's PIF sovereign wealth fund. But the world's top oil exporter has had to rein in some of its ambitious plans over the past year as low oil prices and production continue to hit an economy still reliant on hydrocarbon revenues.

Low oil prices and production have hit Saudi coffers; long-time chief executive Nadhmi Al Nasr leaves due to his inability to deliver key goals, say sources