(Bloomberg) -- Brazil’s congress is set to reject President Jair Bolsonaro’s request to change the country’s voting system, setting the stage for heightened political tension after he argued next year’s elections may be stolen from him without the modification.

Lawmakers will start discussing the bill on the floor of the lower house late on Tuesday and a final vote is expected later in the evening, according to Speaker Arthur Lira. The proposal would mandate a paper printout of each vote electronically cast. As a constitutional amendment, it needs to be approved by 308 of the 513 house representatives in two rounds of voting, before going to the senate. Most political parties in the lower house have announced that they will vote against the bill.

Alarm bells are ringing in Brasilia after the far-right leader suggested that, without paper receipts that could be manually counted, he may not accept the outcome of the election or perhaps not even hold it next year, as mandated by the constitution. An unusual parade of military tanks through the streets of the capital added to the sense of unease, with many politicians describing it as an attempt by the president to intimidate them.

The parade was organized by the navy to invite Bolsonaro and his defense minister to participate in a traditional military exercise that takes place next week. It was the first time, however, that the invitation was delivered with a display of military power in Brasilia. The navy said in a statement it had long planned the event and that it had no relation with votes being carried out in congress.

Yet the event angered lawmakers on both sides of the political spectrum. “It’s a pathetic scene, an attack on democracy,” said Senator Omar Aziz, who presides over the congressional committee investigating the government’s handling of the pandemic.

Even Speaker Lira, a key ally of Bolsonaro, disapproved. In a polarized country such as Brazil, he said, the incident creates speculation that congress may be under some sort of pressure.

Relentless Attack

Brazil’s electronic ballots shifted into the spotlight in recent weeks as Bolsonaro, facing a sharp drop in popularity amid a vaccine-purchasing scandal, launched a relentless attack on their credibility. He has repeatedly claimed, without presenting proof, that the system that has been in use in the country for the past two decades -- and through which he was elected -- is vulnerable to cheating and hacking.

In a report released Tuesday the Brazilian Audit Court said that there are already several safety mechanisms in the current system that allow the voting process and the tallying of the ballots to be audited.

Following in the footsteps of former President Donald Trump, Bolsonaro has been sowing doubt about the integrity of both the country’s voting system and the electoral authority. The strategy has stirred fears that he may be laying the groundwork to challenge the result of next year’s election, should he lose it.

Read More: Bolsonaro Wages Trumpian Campaign to Sow Doubts About Voting

His rhetoric has pushed the country to the brink of an institutional crisis. Last week the Supreme Court’s chief justice canceled plans for a meeting with Bolsonaro and the heads of congress, saying the president seeks to “complicate, frustrate or impede the electoral process.”

Bolsonaro’s focus on the paper-vote issue has also deflected attention from his administration’s erratic handling of the pandemic. An ongoing congressional inquiry is probing allegations of a kickback scheme in the government’s purchase of vaccines, which the president has denied having any knowledge of.

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