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SAO PAULO, March 23 (Reuters) - Brazilian prosecutors said on Wednesday no plea-bargain talks are underway with executives from engineering conglomerate Grupo Odebrecht SA and that the company's public announcement of its intention to cooperate had no legal standing.
Odebrecht, which had previously denied participating in a scheme to siphon money from state-run oil firm Petróleo Brasileiro SA, said late on Tuesday it would cooperate in order to help "build a better Brazil."
"The disclosure of any intended agreement to the press hurts the secrecy of the negotiations required by law to conclude an agreement," the task force of prosecutors based in the southern city of Curitiba said in a statement.
Veja magazine's Radar column had reported that Marcelo Bahia Odebrecht, the company's former chief executive officer and scion of the family that controls the firm, was already testifying before prosecutors. A spokeswoman at Odebrecht did not comment on the report.
Marcelo Odebrecht, sentenced to 19 years in prison for corruption and money laundering, had a close personal relationship with former president Luiz Inacio Lula da Silva. Lula is also under investigation in the scandal and has been charged with money laundering and fraud by state prosecutors.
Odebrecht's testimony could also increase the odds that embattled President Dilma Rousseff does not finish her term.
Political risk consultancy Eurasia Group said it considers Rousseff's ouster "merely a matter of time," and that testimony from Odebrecht could have even more repercussions for Vice President Michel Temer, first in line for the presidency.
Rousseff is trying to survive impeachment hearings in congress for allegedly mismanaging public accounts, but support for her impeachment has grown since Senator Delcidio do Amaral testified that Rousseff knew about the corruption scheme.
Rousseff and Lula deny any wrongdoing.
Prosecutors on Tuesday deepened their investigation of Odebrecht and said they had uncovered systematic corruption, with an office that paid bribes on work for World Cup soccer stadiums and Olympic legacy projects.
The investigation unveiled a scheme in which engineering firms colluded to overcharge Petrobras for work and used the excess funds to bribe officials.
During a raid at the home of another former Odebrecht executive, police found tables with the names of some 200 politicians next to monetary values although it was not clear if these were bribes or legal campaign donations. (Reporting by Caroline Stauffer; Editing by Tom Brown and Sandra Maler)