Brasília (AFP) - Workers erected barricades Sunday along Brasilia's Esplanade of Ministries to separate supporters and opponents of President Dilma Rousseff's impeachment, on the eve of a crucial vote on her political fate.

A congressional commission preparing to recommend whether or not to impeach Rousseff resumes deliberations Monday, with a vote scheduled for 5:00 pm (2000 GMT), and authorities are taking no chances in the build-up to a subsequent vote by the lower house of Congress next weekend.

Officials expect as many as 300,000 people to gather on the esplanade later in the week as the showdown unravels.

"We are aware of this historic moment's importance and are working to provide the necessary conditions for people to exercise their right to freedom of expression without endangering citizens' lives or the integrity of our heritage," Globo G1 website quoted Public Security Secretary Marcia de Alencar as saying.

Rousseff is accused of breaking the law by juggling government accounts to disguise the depth of budget shortfalls during her 2014 re-election.

She argues the relatively technical accusation does not constitute an impeachable offense.

Momentum for Rousseff's removal is fueled by a massive recession, political paralysis and a sprawling corruption scandal that have reduced approval ratings for her government to around 10 percent.

A latest poll by the Datafolha Institute found 61 percent of Brazilians in favor of impeachment, down from 68 percent in mid-March, while 60 percent believe Rousseff should resign.