Brazil's former leader Luiz Inacio Lula da Silva made his return to politics Wednesday attacking President Jair Bolsonaro and his "imbecile" Covid-19 policies, but declined to say whether he would run against him next year.

Lula, who led Brazil from 2003 to 2010, has emerged as a top contender to unseat the far-right incumbent, after a judge annulled the popular but tarnished leftist's corruption convictions Monday, reinstating his right to run for office.

In his first comments since the ruling, Lula, 75, gave a scathing take-down of Bolsonaro's record.

But he declined to formally throw his hat in the ring for the October 2022 elections.

"It would be petty of me to be thinking about 2022 right now," he told a news conference.

"Party leaders need to be talking about vaccines, about salaries."

He was especially biting on Bolsonaro's handling of the pandemic, which has killed nearly 270,000 people in Brazil -- the second-highest death toll worldwide, after the United States.

Bolsonaro, 65, has repeatedly downplayed the new coronavirus, flouted expert advice on containing it and made anti-vaccine comments.

"Don't follow any imbecile decisions by the president of the republic or the health minister: get vaccinated," Lula said.

"The Earth is round, and Bolsonaro thinks it's flat.... Without all this craziness that has swept the country, a lot of deaths could have been avoided."

Bolsonaro fired back that his government "did its part."

"There was never a lack of resources" for the pandemic, he told CNN Brasil.

"Lula's launching his campaign. And since he has nothing to show... it's based on criticism, lies and disinformation."

Lula, a former metal worker and union leader, led Brazil through an economic boom, and is remembered for social programs that helped lift tens of millions of people from poverty.

Brazil's former president Luiz Inacio Lula da Silva, seen here speaking at a press conference on March 10, 2021, has jumped back into politics after a court annulled his corruption convictions
Brazil's former president Luiz Inacio Lula da Silva, seen here speaking at a press conference on March 10, 2021, has jumped back into politics after a court annulled his corruption convictions AFP / Miguel SCHINCARIOL

Recent opinion polls suggest he is the best-placed politician to challenge Bolsonaro's re-election.

But he remains a highly controversial figure after being sentenced to a total of 26 years in jail on charges of taking bribes.

The allegations stem from "Operation Car Wash," an investigation into a corruption scheme in which top politicians and business executives systematically siphoned billions of dollars from state oil company Petrobras.

Lula was jailed in April 2018 -- taking him out of the running for that year's presidential election, in which he was the front-runner -- and spent more than 18 months in prison before being released pending appeal.

Supporters say he was the victim of a conspiracy to eliminate him from the 2018 race, which Bolsonaro ultimately won.

But Lula still faces a series of corruption and influence-peddling charges, including the ones for which he was jailed.

Supreme Court Justice Edson Fachin ruled the court that convicted Lula did not have jurisdiction. But the procedural decision did not rule on the merits of the cases, which will now be transferred to another court.

Lula said he planned to resume touring Brazil once he is vaccinated against Covid-19 next week.

"I still feel young enough to fight, and I want you to know I'll never give up," he said in his trademark gravelly voice, speaking at the headquarters of his former union in Sao Bernardo do Campo, on the outskirts of Sao Paulo.

His speech was fiery at times. But he sought to downplay concerns that he is a radical, presenting himself as a healing figure for a divided Brazil.

"Don't be scared of me. They say I'm a radical because I want to get to the root of this country's problems," he said, dressed in a dark suit of the kind he used to wear to G20 meetings or Davos.

"His speech was a campaign launch" in all but name, political analyst Creomar da Souza, of the consulting firm Dharma, told AFP.

"He presented his project for the country, which involves a lot of references to his legacy as president."

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