Iranian authorities have turned off the lights along Tehran's highways to save energy as the country struggles to cope with a shortage of fuel amid increased demand during winter.
Iran has one of the largest reserves of natural gas but its power sector suffers from a lack of investment, partly because of years of western sanctions.
The highway lights have been switched off for the past two months, deputy director of Tehran's electricity company Alireza Rezaei told official news agency IRNA on Tuesday. Despite safety concerns, the blackout will continue “as long as there is an energy imbalance”, he said.
Mr Rezaei said two-hour power cuts were planned at different times in different locations, and residents would be notified in advance by text message.
Iran's traffic police warned that the lack of lighting would increase road accidents and crime at night, while Tehran's city council urged police to use warning lights to make road signs visible to drivers.
“We have repeatedly warned about lights being off and I wish these lights would use solar energy so that we would no longer witness them being cut off,” Mehdi Chamran, head of Tehran City Council, was quoted as saying by the Isna news agency.
Iran's Communications Ministry reported disruptions to phone and internet services because of power cuts. Schools and public offices across most of the country were closed for a third consecutive day on Tuesday, and authorities also reduced the opening hours of shopping centres.
Sub-zero temperatures in the majority of Iran's 31 provinces have added to the burden on energy supplies, according to state media. Energy Minister Abbas Aliabadi called for people's co-operation in decreasing fuel consumption, attributing the current shortage to air pollution and changes in weather which led to a surge in demand for electricity.
President Masoud Pezeshkian, an advocate of reducing fuel consumption, urged Iranians to wear warmer clothes at home to reduce the need for heaters. He apologised to the nation on Monday and promised that the issue would be resolved in the coming year.
Gas-fuelled power plants in Lorestan and Golestan provinces were partially shut down earlier this week in what the government framed as an environmental protection measure. Last month, Iran said it halted gas exports to Iraq in order to carry out pipeline repairs.
Oil Minister Mohsen Paknejad said Iran country was close to securing imports of electricity to meet the high demand, without mentioning the supplier countries. Iran imported electricity from Turkmenistan in June to meet the high demand during summer.
