Venezuelan President Nicolas Maduro put the country's electricity supplies on an emergency footing after Caracas and outlying areas plunged into darkness amid repeated blackouts.

Power cuts were a recurring problem for late President Hugo Chavez, who struggled to restore the oil-rich nation's energy sector back on track after a series of disastrous nationalizations.

Critics of Chavez say Venezuela's infrastructural problems, including power cuts, contributed to the country's economic downturn.

Chavez died of cancer in March. His named successor Maduro won a narrow vote this month to continue Chavez's term in office in a controversial constitutional arrangement denounced by the opposition.

Maduro said a 90-day state of emergency in the country's power sector would allow the government to address infrastructural problems. The government is importing new equipment to upgrade run down power generation installations seen behind the frequent breakdowns.

For years critics of Chavez, who ruled from 1999 to his death, accused the government of squandering national oil wealth on populist programs instead of building the country's infrastructure.

Loyalists of the former president's Bolivarian revolution counter the government's huge cash handouts have lifted Venezuelans out of poverty.

Despite a tacit recognition of systemic failures during the period, officials continue to berate Venezuelans for excessive consumption and claim frequent sabotage by unnamed opposition elements is also behind the breakdowns.

Critics say poor management of nationalized enterprises, inefficiency and waste in the state-controlled energy sector are to blame for frequent interruptions in power supply, seen to disrupt businesses, industry and schools.

Maduro has promised to address inefficiencies and correct infrastructural flaws. However, Maduro's combative manner has drawn comparisons with Chavez's style of government, which targeted businesses and senior management of state-owned enterprises in times of crises.

Maduro's call to the armed forces to guard distressed energy installations against possible sabotage has raised the possibility of a purge of senior officials in a troubled state sector.

A government decree ordered state-owned Corpoelec electricity company to spare no technical or economic effort to bring power generation back to normal.

Critics say the power industry's main problems lie in a shortage of trained staff that got shunted aside in waves of nationalizations and a chronic inability of state enterprises to requisition timely replacements for faulty spare parts.

Once again officials have blamed overconsumption as one of the chief causes of power shortages.

Maduro called on Venezuelans to support him in a nationwide drive to encourage a "rational" use of the utilities.

As in the past, critics say the government's exhortations are often hard to interpret and energy saving programs are difficult to enforce without risks to continued operation of industry and essential service sectors.