Brazilian state-run energy giant Petroleo Brasileiro (PBR, PETR4.BR), or Petrobras, said Wednesday that crude oil and natural gas production sank in July on maintenance stoppages at several offshore platforms.

Petrobras produced an average 2.568 million barrels of oil equivalent, or BOE, per day in July, down 2.8% from 2.641 million BOE per day in June. The company's domestic crude oil output was 3.9% lower month-on-month in July at an average of 1.968 million barrels a day, down from 2.047 million barrels a day in May.

The decline in output was attributed to ongoing maintenance work at several key offshore fields in the
Campos Basin , where more than 85% of Brazil 's offshore crude is produced, Petrobras said. The company had embarked on a heavy round of maintenance work at its offshore platforms in the first half of 2011.

Natural gas production also decreased slightly in July, Petrobras said. The federal oil company produced a daily average of 74.0 million cubic meters of natural gas at home and abroad.
That was down from 74.5 million cubic meters in June.