Speaker Eduardo Cunha has denied bribery and money laundering allegations in the "Car Wash" probe.
Rio de Janeiro CNN  — 

The corruption investigation that’s spread like wildfire through Brazil’s most powerful political circles claimed another casualty Thursday with the suspension of the top lawmaker behind the drive to impeach the President.

Supreme Court Justice Teori Zavascki suspended Eduardo Cunha, speaker of the lower house of Congress, from all congressional duties for allegedly obstructing corruption investigations and intimidating lawmakers. The move comes weeks after Cunha led a charge to impeach President Dilma Rousseff in the Chamber of Deputies.

A sworn rival of Rousseff’s, Cunha spearheaded efforts to launch an impeachment motion against the President over allegations she manipulated the federal budget to hide a shortfall ahead of the 2014 elections. The Chamber of Deputies moved to impeach Rousseff in a two-thirds vote April 17.

Zavascki made the temporary ruling on Cunha on Thursday morning, according to the court’s website, and the matter will be addressed further during a full session later Thursday.

The decision comes after the Brazilian prosecutor general accused Cunha of trying to interfere with investigations into a massive kickback scheme at the state-run oil company Petrobras.

Cunha has been formally accused of bribery and money laundering as part of the “Car Wash” probe but has fought to hang onto his congressional seat. He denies the allegations.

The motion to impeach Rousseff will be voted on in the Senate next week. It is widely expected to be approved, which will mean the President will have to step down for up to 180 days to defend herself in an impeachment trial.

Vice President Michel Temer would then become interim president. And Cunha, as head of the lower house of Congress, would have been second in line.

The President and her supporters have called the impeachment proceedings an institutional coup d’etat by lawmakers accused of far more serious crimes who are seeking revenge.