Pakistan's national power grid was restored on Tuesday, a day after a nationwide blackout left the country's 220 million residents in the dark.
The power cut, which started at 7.30am local time (2.30am GMT) on Monday caused tens of millions of dollars in industry losses, and has been linked to a cost-cutting measure.
This grid failure forced businesses to switch to backup generators, and caused major disruption to mobile and internet services.
The grid was repaired at 5.15am, Energy Minister Khurram Dastgir Khan said, but power cuts will continue over the next two days as coal and nuclear plants are brought back online.
"Industry will be exempt from this load-shedding," AFP reported Mr Khan saying in Islamabad.
Schools, hospitals, factories and shops were without power amid the harsh winter weather, AP reported.
Secretary general of the All Pakistan Textile Mills Association, Shahid Sattar, estimated losses of $70 million to the sector, which is Pakistan's largest exporter and a crucial booster of foreign exchange reserves.
About 90 per cent of factories shut down on Monday with gas supplies being too "patchy" to stand in, he said.
The precise cause of the grid failure remains unknown and PM Shehbaz Sharif has ordered an investigation.
This will assess whether external hacking could have been a contributor, Mr Khan said.
He had earlier pointed to a period of low demand and a decision to save costs by taking some plants offline as potential catalysts.
Pakistan is grappling with a series of energy challenges, including ageing electricity transmission infrastructure has suffered repeated recent failures and a major breakdown of the national grid in January 2021.
