Lawmakers vote on the impeachment of the Brazilian President Dilma Rousseff during a session of the parliamentary committee at the Chamber of the Deputies in Brasilia, Brazil, on April 11, 2016. A Brazilian congressional commission recommended impeachment against President Dilma Rousseff in a vote on Monday. The commission voted 38 to 27 to support the impeachment, setting the tone for the full lower house to vote on Sunday whether Rousseff should face trial. [Photo/Xinhua]

BRASILIA - Brazil's Chamber of Deputies (the lower house of parliament) announced Tuesday it is set to vote Sunday on whether or not to launch an impeachment process against President Dilma Rousseff.

Eduardo Cunha, president of the Chamber of Deputies, told Brazilian lawmakers they would begin to debate the issue early Friday and put it to a vote Sunday night.

If the chamber votes in favor of the impeachment, the motion then will go to the Senate, where it will be debated and voted on again before a congressional impeachment process can begin.

Rousseff's political opponents said her administration inflated the public accounts prior to her run for re-election in 2014, and generally mismanaged the economy.

Rousseff refuted the charges, describing the push for the impeachment as a "coup" by rival political groups for grabbing power.

At a meeting Tuesday with members of the educational sector which assembled at the presidential headquarters in a show of support, Rousseff said: "Now they are openly conspiring, in broad daylight, to destabilize a legitimately elected president."

A day earlier, Brazilian media outlets published a leaked audio of the estranged vice president, Michel Temer, who rehearsed a post-impeachment speech to the nation, calling for national unity.

The audio made Temer appear overly keen to fill in as president while Rousseff undergoes an impeachment or is eventually forced out of office.

Also on Tuesday, Ernesto Samper, secretary general of the Union of South American Nations (Unasur), expressed concern that a politically-motivated impeachment drive could undermine judicial institutions in Brazil and the region.

In a statement issued at the Unasur headquarters in Quito, Ecuador, Samper noted the lawmakers were pursuing a trial "without any evidence that personally and directly incriminates (Rousseff) in committing a crime."

"The president can only be tried and ousted ... for crimes in which her active and willful participation can be proven," he added.

Accepting that a head of state "can be ousted from office for alleged administrative failures would lead to the dangerous criminalization of governing," driven by political motives, said Samper.

A two-third majority of the lowe house, or 342 of the 513 deputies, are needed to pass the impeachment motion.

Members of the Workers' Party and affiliated political groups that form the ruling coalition fear Cunha will try to manipulate the voting in favor of the impeachment by trying to have the representatives of Brazil's wealthier conservative southern states vote first, which will possibly give the impeachment greater momentum.