People walk past a billboard in Caracas with an image of Venezuelan opposition leader Leopoldo López, who was granted house arrest on Saturday after more than three years in jail. (Marco Bello/Reuters) (Marco Bello/Reuters)

The Venezuelan government freed its fiercest political rival early Saturday in a surprise move, allowing opposition leader Leopoldo López to leave his prison cell and return home after nearly three and a half years behind bars.

Venezuelan authorities called the decision a humanitarian gesture, citing López’s allegedly poor health, but his supporters celebrated his release as a capitulation by the embattled government. Concerns about López’s well-being were calmed when he briefly appeared before cheering crowds outside his family home, waving a Venezuelan flag and thrusting a defiant fist skyward.

He did not address the crowd, and the conditions of his transfer from prison to house arrest were not immediately known.

López, Venezuela’s most prominent political prisoner, was arrested in early 2014 and handed a 13-year jail term. He became a symbol of resistance for opponents of the government, his portrait printed in bright colors on the T-shirts and flags of protesters who chant, “Free Leopoldo!”

López, 46, was escorted out the prison at about 3 a.m. under cover of darkness, and news of his release was applauded by governments across the hemisphere, which called on Venezuelan authorities to release others held on politically related charges.

For Venezuelan President Nicolás Maduro, the move to free López presents a significant political risk. The charismatic former Caracas mayor ranks in polls as the country’s most popular politician, and in a statement from López read by fellow opposition leaders Saturday, he said he was not afraid to return to jail.

“If continuing my fight for freedom means going back to [prison] I am ready to do it,” his statement read. “I reiterate to you my commitment to fight for freedom.”

López’s supporters were quick to point out that while the conditions of his confinement had changed, his conviction — on charges of inciting violence during 2014 protests — had not been lifted. His ability to assume leadership of the new protest movement against Maduro could be limited by the terms of his house arrest.

His father, Leopoldo López Gil, told reporters that authorities placed an electronic monitoring bracelet on his son, “but outside of that we don’t know of any other limitation,” he said, speaking from exile in Spain.

“What happens now depends very much on what Leopoldo is allowed to do and whether he will have the freedom to exercise leadership of the opposition,” said Caracas political analyst Carlos Romero.

Many said they were puzzled by the government’s sudden decision to release him, but a statement by Defense Minister Vladi­mir Padrino Lopez crediting international mediators appeared to offer insight into Maduro’s thinking.

“Today the country woke up to a gesture that was the result of dialogue,” Padrino Lopez said, praising mediators led by former Spanish Prime Minister Jose Luis Rodríguez Zapatero.

Yet years of failed attempts at mediation have convinced many government opponents that such calls are hollow and cynical attempts to buy more time. They called Maduro’s decision the result of growing domestic and international pressure on the cash-strapped government to return to democratic norms.

[Venezuela’s slide into chaos is splintering the Chavez movement]

In a statement to reporters, López’s staff described his release as a “unilateral” decision by the government, not the result of a quid pro quo negotiation.

Venezuela has been on a hair-trigger in recent weeks, as the Maduro government pushes forward with a widely condemned plan to hold a “constituent assembly” that will have the power to rewrite the country’s constitution. The government has set July 30 as the date for voters to begin electing delegates to the assembly, which opponents of the government say they will boycott.

On Wednesday, armed pro-government supporters forced their way inside Venezuela’s parliament and beat up several opposition lawmakers, a shocking attack that deepened fears of an increasingly bloody confrontation. Nearly 100 Venezuelans have died in the past three months of political unrest, with near-daily clashes between protesters and security forces.

[Government supporters attack Venezuelan congress, injure opposition lawmakers]

Letting López out of prison seems unlikely to cool the streets, analysts said, nor convince Maduro’s critics that his government has had a sudden democratic awakening.

“Did the government merely do this to relieve some international pressure?” said Phil Gunson, a Caracas-based analyst for the International Crisis Group. “Seems hardly plausible, since by conceding this major point they only encourage the opposition — internal and external — to go for more.”

Opposition leaders pledged to continue marching, urging Venezuelans to join them in “100 days of struggle” that would kick off with mass demonstrations Sunday morning.

Rachelle Krygier contributed to this report from Madrid.

Read more:

How a new kind of protest movement has risen in Venezuela

Venezuela’s paradox: people are hungry, but farmers can’t feed them

Venezuela may be sliding toward civil war

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