Armed groups increasingly control the antiquated switching stations that channel electricity around Iraq, the electricity minister said Wednesday. That is dividing the national grid into fiefs that, he said, often refuse to share electricity generated locally with Baghdad and other power-starved areas in the centre of Iraq.

The development adds to existing electricity problems in Baghdad, which has been struggling to provide power for more than a few hours a day because insurgents regularly blow up the towers that carry power lines into the city.

The government lost the ability to control the grid centrally after the American-led invasion in 2003, when looters destroyed electrical dispatch centres, the minister, Karim Wahid, said in a news briefing attended also by United States military officials.

Because of the lack of functioning dispatch centres, Wahid said, ministry officials have been trying to control the flow of electricity from huge power plants in the south, north and west by calling local officials there and ordering them to physically flip switches. But the officials refuse to follow those orders when the armed groups threaten their lives, he said, and the often isolated stations are abandoned at night and easily manipulated by whatever group controls the area.

This kind of manipulation can cause the entire system to collapse and bring nationwide blackouts, sometimes seriously damaging the generating plants that the United States has paid millions of dollars to repair. Such a collapse took place just last week, the State Department reported in a recent assessment, which said the provinces’ failure to share electricity resulted in a “massive loss of power” on August 14 at 5 pm.