BRASILIA (AFP) - Brazilian lawmakers relaunched impeachment proceedings against President Dilma Rousseff on Thursday and a judge blocked her bid to bring her powerful predecessor into her cabinet, intensifying the political crisis engulfing her.

The fresh setbacks for the 68-year-old leftist leader struck a day after fresh street protests erupted, sparked by new evidence in a state corruption scandal that pointed to connivance between Rousseff and her predecessor and mentor, Luiz Inacio Lula da Silva.

Just hours after Rousseff swore in Lula, 70, as her new chief of staff on Thursday, a judge issued a ruling suspending the appointment over allegations that she was trying to protect him from corruption charges.

Rousseff accused her enemies of mounting a "coup" against her.

Lula's new position would grant him ministerial immunity, protecting him from prosecution in criminal court.

Rousseff got as far as giving Lula a post-ceremony hug before federal judge Itagiba Catta Preta suspended the ex-president's nomination to the Cabinet chief post "or any other that grants him immunity."

Government lawyers promptly launched an appeal against that preliminary injunction, which applies until a definitive court ruling on the matter.

Shortly after the injunction, Brazil's lower house of Congress launched a committee to consider impeaching Rousseff over corruption accusations in a separate case.

She is accused of manipulating the government's accounts to boost public spending during her 2014 re-election campaign.

The drive to impeach her was launched by the opposition in December but had been put on hold by the courts over procedural issues.

The courts finally ruled late Wednesday on regulations authorizing lawmakers to carry out the procedure.

Thursday's events plunged Rousseff's tottering government into even deeper uncertainty as the president battles deep-seated public anger, a deep recession and the splintering of her coalition.

Lula and Rousseff have between them governed Brazil for the past 13 years. Lula presided over a boom, but political and economic crises are now gripping the once-booming Latin American giant.

Protests erupted Wednesday when an anti-corruption judge leaked a damning wire-tapped phone call between Rousseff and Lula, suggesting she appointed him to save him from arrest.

"Shame!" shouted a protester as Lula was sworn in. The ex-president's supporters chanted slogans accusing their opponents of seeking a coup.

"The putschists' shouting won't make me veer from my path or bring us to our knees," said Rousseff.

"If they violate the rights of the president, what will they do with those of the citizens? That is how coups start."

Lula, who led Brazil from 2003 to 2011, is charged with accepting a luxury apartment and a country home as bribes from executives implicated in a multi-billion-dollar corruption scam at state oil company Petrobras.

Rousseff vehemently denies trying to help him dodge prosecution, insisting she needs Lula, "this country's greatest political leader," to help rescue her government from crisis.

But hours after Lula's nomination Wednesday, federal judge Sergio Moro, who is heading the explosive Petrobras probe, ordered the release of evidence suggesting darker motives.

Rousseff called Lula's bugged phone to tell him she would be sending him the official decree nominating him as her chief of staff so he could make use of it "if necessary."

Cabinet ministers can only be tried before the Supreme Court in Brazil, and ministerial immunity would protect Lula from criminal court.

Lula denies involvement in the scandal. Investigators say construction companies conspired with Petrobras executives to overbill the oil giant to the tune of $2 billion, paying huge bribes to politicians and parties along the way.

Rousseff's office said the phone call was about a simple procedural matter and accused Moro of a "flagrant violation of the law and the constitution."

The recording caused thousands of people to flood into the streets to protest in cities including the capital Brasilia and the largest city Sao Paulo.

Some three million Brazilians also protested Sunday in nationwide demos calling for Rousseff's departure.

The leaked wiretap also caused uproar in Congress, where furious opposition lawmakers shouted "Resign! Resign!"