Minister says restoration work could take up to 12 hours, adding that a limited number of power grids are back on.

In a statement on Twitter, the energy ministry said the system frequency of the national grid went down at 7:34am (02:34 GMT) on Monday morning.

“System maintenance work is progressing rapidly,” the tweet added.

Power minister Khurram Dastagir told a local TV channel that the national grid switches off power generation units temporarily at night during the winter to save fuel costs.

“However, this morning, when the systems were turned on at 7:30am one by one, frequency variation was reported in the southern part of the country between Jamshoro and Dadu,” he said, referring to the two towns in the southern Sindh province

“There was a fluctuation in voltage and power generating units were shut down one by one due to cascading impact. This is not a major crisis,” he said.

Dastagir said restoration work could take up to 12 hours, adding that a limited number of power grids are back on.

The power outage in the country of more than 220 million people came amid an economic crisis.

Earlier this month, the government passed a directive, asking markets and shopping centres to close by 8:30pm in order to save energy amid an escalating fuel crisis. However, the appeal was ignored.

This is the second time in the last four months that Pakistan was hit by a major power breakdown.

The outage in October lasted for more than 12 hours and mainly affected the southern parts of the country, including its largest city, Karachi, home to 15 million people.