BRASILIA, March 24 (Reuters) - Standard & Poor's cut the ratings of Brazilian state-run oil company Petroleo Brasileiro SA and Brazils largest utility Eletrobras to BBB- from BBB on Monday in line with its earlier decision to downgrade the country's sovereign debt.
The agency cut Brazil's long-term debt rating one notch to BBB-, its lowest investment-grade, due to mixed policy signals from President Dilma Rousseffs government that had undermined its fiscal credibility and a slow growth outlook for the next two years.
S&P also cut the credit rating of mining company Samarco, which is owned by Vale and BHP Billiton (NYSE: BBL - news) , to BBB- from BBB. The outlook for all three Brazilian companies is stable, the agency said.
(Reporting by Anthony Boadle; Editing by Michael Perry)