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President Hugo Chavez suspended rolling blackouts in Venezuela's capital a day after they began and sacked his electricity minister, saying government officials imposed a rationing plan riddled with mistakes.

Chavez's announcement late Wednesday was a significant shift in his attempts to avoid a widespread power collapse in the coming months through rolling blackouts of up to four hours a day throughout the country. Other rationing measures are to remain in place, including outages in other areas.

"I have ordered the electrical outages to be suspended, only in Caracas," Chavez said on state television. "Because this government has to be capable of recognizing mistakes made and fixing them in time."

The rolling blackouts have been unpopular in a city already plagued by violent crime, traffic and trash-strewn streets, and opposition leaders accused Chavez on Thursday of backtracking to try to head off damage to his political support.

But the president cited tactical errors instead, saying power was cut in the wrong sectors of the city in some cases.

"I think in one area they repeated the outage a few hours later," he said. He added that some stoplights also went dark.

"Enough. I said if that's what is going on, there was an error there," Chavez said.

Chavez said he asked Electricity Minister Angel Rodriguez to resign and that "he has taken it like a soldier."

Chavez said he ordered the blackouts "interrupted indefinitely" in Caracas and told the city's state electric utility not to schedule any more until the process is reviewed. It was unclear when or if the government may attempt to restart the measures.

The government says energy rationing is necessary to prevent a widespread collapse if the water levels behind Guri Dam -- which supplies most of Venezuela's electricity -- fall to critical lows in the coming months due to a severe drought. Officials also acknowledge that some gas- and oil-fueled thermoelectric plants are producing below capacity while undergoing repairs.

Caracas Mayor Antonio Ledezma, a Chavez opponent, said the government was forced to call off rationing in the metropolitan area of about 6 million people because it was highly unpopular. He urged Venezuelans to join a protest this weekend against faulty public services, water and electricity rationing and a currency devaluation expected to drive up already-soaring inflation.

"We have to defend the citizens of all of Venezuela's states," Ledezma told the television channel Globovision.

Noel Alvarez, president of the country's largest business chamber, said the government is far from resolving the energy crisis and still must "present clear and concrete solutions."

Chavez announced he was calling off the blackouts in Caracas just hours after he urging Venezuelans to accept the cutbacks and likened them to a national energy diet. He called a late-night talk show to announce the change shortly before some parts of Caracas were to begin four-hour outages at midnight.

The government also has reduced the hours of electrical supply for stores in shopping malls and required businesses and large residential complexes to cut usage by 20 percent or face fines. Chavez reduced the workday of many public employees, setting new hours from 8 a.m. to 1 p.m.

The state electrical corporation said Thursday it is cutting the amount of power it exports to the Brazilian city of Boa Vista by 70 percent to 20 megawatts.

Critics blame Chavez's government for the shortage, saying it has failed to complete enough power upgrades to keep up with increasing demand.

Chavez denies that, saying the drought is the primary culprit and that his government is acting to extend the Guri Dam's capacity to feed the electrical grid. Rains are expected to return at the end of the traditional dry season in May.

Energy analyst Victor Poleo said the government's rationing measures are not enough to make up for the expected gap between supply and demand.

"Rationing in the city of Caracas is useless considering the size of the deficit," said Victor Poleo, an oil economics professor at Venezuela's Central University and a former official in Chavez's Energy Ministry.

He said gas- and oil-fired plants would be able to cover only about 20 percent of domestic demand if the Guri Dam's hydroelectric plants are idled.