Caracas (AFP) - With their country gripped by an economic crisis, Venezuelans lost half an hour of sleep Sunday as their clocks were set forward to save power on President Nicolas Maduro's orders.

At 2:30 am local time, the oil-dependent South American nation shifted its time ahead by 30 minutes -- to four hours behind Greenwich Mean Time.

The move, announced in mid-April, is part of a package of measures the embattled socialist president is pursuing to cope with a crippling electricity shortage.

Maduro's government has also instituted four-hour daily blackouts across most of the country, reduced the public-sector workweek to two days and ordered schools closed on Fridays -- adding to the woes of a nation already stuck in a crushing recession.

The power cuts sparked riots and looting this week in Venezuela's second-largest city, Maracaibo.

In announcing the time change, the government said 30 extra minutes of daylight at the end of the day would curb the use of lights and air conditioning, especially draining for the power grid.

A video posted on Twitter showed the man charged with keeping the official time in Venezuela, Jesus Escalona, adjusting the atomic clock at the Cagigal Naval Observatory in Caracas.

"Venezuela has half an hour more future," Maduro said in a speech to thousands of supporters during a May Day rally at the presidential palace.

Maduro's late predecessor, Hugo Chavez, implemented the unusual half-hour time shift in December 2007, saying he didn't want children to have to walk to school in the dark. Chavez died in 2013.

Maduro blames the power crunch on the El Nino weather phenomenon, which has unleashed the worst drought in 40 years, reducing the reservoirs at Venezuela's hydroelectric dams.

But the opposition says mismanagement is to blame for the power crisis as well as the recession and shortages.

- May Day pay raise -

Speaking in a national broadcast on the eve of International Workers' Day, Maduro decreed a 30-percent increase in the minimum wage.

Story continues

While the pay bump may seem substantial, it brings the minimum wage to the equivalent of $40 a month at the official exchange rate, or just $14 a month at the black-market rate.

The minimum wage had already been increased by 56 percent earlier this year. The raises are far from keeping pace with inflation, which came in at 180.9 percent last year and is forecast by the International Monetary Fund to hit 700 percent this year.

Once-booming Venezuela, which has the world's largest proven oil reserves, has plunged into economic chaos as global crude prices have collapsed. It has been in recession since 2013.

The import-dependent country faces acute shortages of food and basic goods like toilet paper because of a shortage of hard currency, more than 96 percent of which it gets from oil sales.

- Maduro warns of 'rebellion' -

Maduro has vowed to press on with the socialist "revolution" launched by Chavez in 1999, which has given Venezuela a government-led economy.

The opposition -- emboldened by winning the legislature in elections last December -- is pushing to drive Maduro from office.

Opponents say they have gathered more than 10 times the roughly 200,000 signatures needed to begin organizing a referendum to remove him.

If the electoral board accepts the signatures as valid -- far from a sure bet, since opponents criticize it as loyal to Maduro -- the opposition will then have to collect four million more for the board to organize the vote.

Opponents are racing to hold a referendum before the end of the year. After January 2017, a successful recall vote would transfer power to Maduro's vice president rather than trigger new elections.

A recent poll found that more than two-thirds of Venezuelans want Maduro to leave office.

He called on his supporters to wage a "rebellion" if he is ousted, amid fears of a repeat of protest violence that left 43 people dead in 2014.

"If the oligarchy someday does something against me and manages to take this palace, I order you to declare yourselves in rebellion and decree an indefinite general strike," he said, calling himself "the most-attacked human being in Venezuela."