Brasília, Brazil - Brazil's Supreme Court on Tuesday ruled that former president Jair Bolsonaro's coup conviction was final, with no more appeals allowed, clearing the way for him to begin serving a 27-year sentence.

Bolsonaro (70) was in September convicted over a scheme to stop leftist Luiz Inacio Lula da Silva from taking office after the 2022 elections, and that included an assassination plot.

The Supreme Court rejected an appeal to his sentence earlier this month, and ruled the judgment was now final.

The former army captain who fired up Brazil's conservatives to become president in 2019 and reshaped the country's politics will now have to serve the lengthy jail term.

Bolsonaro had been under house arrest until Saturday, when he was detained at police headquarters in the capital Brasília for tampering with his ankle monitor using a soldering iron.

Supreme Court judge Alexandre de Moraes said there had been "very serious indications of a possible attempt to flee" during a planned vigil organized by Bolsonaro's son outside his home.

The justice pointed to the location of the nearby US embassy, and Bolsonaro's close relationship with US President Donald Trump, suggesting he may have tried to escape to seek political asylum.

During a hearing on Sunday in Brasília, Bolsonaro stated he "experienced a certain paranoia between Friday and Saturday due to medication," according to a Supreme Court document obtained by AFP.

He also asserted "that he had no intention of fleeing and that there was no breakage of the bracelet's strap."

In a video made public by the court on Saturday, Bolsonaro gave a different version of events: he said he had used a soldering iron on the monitoring bracelet out of "curiosity."