A girl walks on a darkened street after a power outage in Baghdad, Iraq, on Aug. 11, 2025. [Photo/Xinhua]

A sudden failure in Iraq's power transmission lines on Monday triggered a nationwide blackout, the Electricity Ministry said.

Mohammed Nema, undersecretary for production affairs at the ministry, said technical teams were working to repair the fault and had begun gradually restoring service, which was expected to be fully restored within hours.

Ministry spokesperson Ahmed Musa told the state-run Iraqi News Agency that the outage was caused by an overload in the power system, particularly in Babylon province and the Shiite holy city of Karbala, where millions of pilgrims have gathered for the Arbaeen religious ritual.

He said record-high temperatures, surging demand, and increased electrical loads disconnected transmission lines, cutting more than 6,000 megawatts from the grid. The sudden drop, he added, accelerated the frequency of generating units, triggering their automatic shutdown.

Iraq has been hit by a severe heatwave in recent days, with temperatures reaching around 50 degrees Celsius in several provinces, further straining the country's power supply.