BRASILIA - Brazil's Federal Supreme Court on Friday authorized former President J to undergo surgery, as President Luiz Inacio Lula da Silva vowed to veto a congressional bill that could reduce sentences for Bolsonaro and others convicted of an attempted coup.

Judge Alexandre de Moraes, overseeing Bolsonaro's case, ruled that the former president, currently serving a 27-year and three-month sentence for leading the 2022 attempted coup, may have the surgery recommended by a Federal Police medical board. The procedure is to treat a bilateral inguinal hernia and, while not an emergency, should be performed "as soon as possible" to prevent complications.

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In the same decision, Moraes denied the request for house arrest presented by the former president's defense.

Lula reaffirmed on Friday that he would veto a congressional bill that revises certain sentencing calculations, which could reduce prison terms for Bolsonaro and other coup convicts.

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"With all due respect to the deputies and senators who voted for the sentence reduction, I want to tell them that I will veto that law," Lula stated during an event in Sao Paolo.

Lula added, however, that if he issues a veto, Congress would still have the authority to override it in a subsequent vote -- a step that could benefit Bolsonaro.