Announcement comes as Juan Guaidó’s wife met with Donald Trump and Vice-President Mike Pence in Washington

The opposition figurehead battling to topple Nicolás Maduro has told supporters to prepare for a final nationwide push against Venezuela’s authoritarian leader after the country suffered its fourth massive blackout in less than three weeks.

Addressing a rally in Caracas, Juan Guaidó said it was time for Venezuelans of all social classes to increase pressure through what he called Operación Libertad (Operation Freedom) – a mobilization across the country that would culminate in a massive march through the capital.

Vice-president blames ‘fascist right’ and its ‘imperial masters’ in Washington for power cuts

Nicolás Maduro’s embattled administration has called for calm after millions of Venezuelans were again plunged into darkness by a nationwide blackout reportedly affecting 21 of its 23 states and the capital, Caracas.

In a late-night television broadcast – which most people were unable to watch because of the outage – the communications minister, Jorge Rodríguez, claimed it was the result of a “brutal” attack on a hydroelectric plant on Monday night.

Embattled president hints that Juan Guaidó and allies are in his sights

Venezuela’s opposition is bracing for a severe political crackdown after Nicolás Maduro lashed out at the “diabolical pro-imperialist puppets” he claimed were trying to remove him from the presidency and vowed to imprison them all.

The struggle between Maduro and his challenger, Juan Guaidó, escalated dramatically last week with the detention of Guaidó’s right-hand man, Roberto Marrero.

Maduro’s interior minister alleged a cache of ‘weapons of war’ had been apprehended with Roberto Marrero as face-off escalates

The face-off between Nicolás Maduro and his US-backed challenger Juan Guaidó has escalated dramatically after Venezuelan intelligence agents seized Guaidó’s chief of staff and accused him of leading a “terrorist cell” plotting a wave of political assassinations.

Related: Juan Guaidó's chief of staff arrested by Venezuelan agents

Power outage – that Maduro blames on foreign saboteurs – could have dramatic implications for country’s political future

When night falls on Venezuela’s ghostly capital, an unnerving hush grips the streets of this once-bustling South American metropolis.

“You feel a profound silence all around you,” said Alejandro Guzmán, a 26-year-old lawyer and one of millions of Venezuelans left in the dark after their country was hit by an unprecedented blackout some believe could have dramatic implications for its political future. “It’s like a city of shadows.”

Demonstrations spark fears country’s political crisis could deep following huge blackout

Supporters of Venezuela’s leader, Nicolás Maduro, and his US-backed challenger, Juan Guaidó, returned to the streets again on Saturday amid rising fears the political crisis could be entering a turbulent new phase.

After a strained 48 hours for Venezuela in which almost the entire country was affected by a blackout thousands of demonstrators turned out to champion their respective leaders, both of whom claim the presidency.

Delcy Rodríguez said schools were closed and workers should stay home after ‘technological attack’ on Guri hydroelectric plant

Venezuela’s embattled president, Nicolás Maduro, has been forced to close schools and give workers the day off after a severe and potentially destabilizing blackout dragged into a second day.

On Friday morning, more than 19 hours after power failed across most of the country, Venezuela’s vice-president, Delcy Rodríguez, announced that schools would not open and private- and public-sector workers should stay at home.

Washington warned on eve of arrival Maduro faces ‘strong and significant response’ if Guaidó is detained or threatened

The opposition figurehead battling to dislodge Venezuela’s president Nicolás Maduro has made an audacious and dramatic homecoming, flying into the country’s main airport as he sought to re-energize his campaign for political change.

Juan Guaidó – who secretly left Venezuela last month to conduct a support-seeking tour of South America – landed at the Simón Bolívar international airport on Monday on a commercial flight from Panama.

• Opposition leader set to meet Vice-President Mike Pence
• Comments come a day after clashes that left four people dead

Venezuelan opposition leader Juan Guaidó is set to meet US Vice-President Mike Pence on Monday, after asking other countries to consider “all options” to remove President Nicolás Maduro from power.

Related: 'Venezuelan blood is being spilled': tension flares near border with Brazil