President Dilma Rousseff voiced confidence Friday that Brazil's people will "be able to prevent any setbacks" to democracy as she battles a bid to impeach her.

"Brazil is a great country endowed with a society that was able to overcome authoritarianism in the past," Rousseff said at the United Nations during a ceremony for the signing of the Paris climate deal.

"Ours is a hard-working people. We have great esteem for freedom. I have no doubt that our people will be able to prevent any setbacks," she said.

Rousseff is fighting for her political survival at home following allegations that she used illegal accounting maneuvers to mask budget deficits during the 2014 election year.

The leader has denied the charges and spoke of a "grave, serious moment" in Brazil at the end of her remarks devoted mostly to climate change.

The president thanked "all the leaders who have expressed their solidarity to me."

After leaving the UN, Rousseff raised the tone when speaking with Brazilian media, repeating her claim of a "coup" attempt against her, and calling for regional bodies Mercosur and UNASUR to oversee the process.

"I am a victim of a totally unfounded process," she said. "You cannot cover the sun with a finger."

While in New York, Rousseff left Vice President Michel Temer in charge even though she has accused him of conspiring to oust her.

The Brazilian Senate is due to vote on opening a trial next month, a move that would force Rousseff to step aside for 180 days and put Temer back in the executive office.

After that, a two-thirds majority vote would be enough to oust her permanently, leaving Temer to serve out her term, which ends in late 2018.