BRASILIA, Feb 19 (Reuters) - Brazil Supreme Court Judge Teori Zavascki on Friday ordered the release of ruling party Senator Delcidio do Amaral, who has been jailed since November and faces charges of obstructing a massive corruption investigation, a court representative said.
Amaral's arrest, part of the ongoing probe into kickbacks around state-run oil company Petroleo Brasileiro SA, complicated President Dilma Rousseff's effort to pass unpopular austerity measures. The senator had been her main negotiator on economic policy in Congress.
A spokeswoman for the Supreme Court said Amaral would likely be released later on Friday and would be able to return to Congress.
The judge imposed some restrictions, saying Amaral must appear in court every 15 days and would not be allowed to leave Brazil.
Zavascki authorized Amaral's arrest, the first of a sitting senator in Brazil's modern history, on Nov. 25. Prosecutors allege Amaral tried to bribe Nestor Cervero, a former executive at Petrobras, as the oil company is known, to keep Cervero from signing a plea deal.
Dozens of engineering firm executives and senior politicians have been arrested or are under investigation in Brazil, mostly on charges of colluding to overcharge the oil company and using the proceeds to bribe members of Rousseff's coalition. (Reporting by Maria Carolina Marcello and Caroline Stauffer; Editing by Matthew Lewis)