It made 10.9bn reals ($6.9bn; £4.3bn), but the increase was down to a 2.9bn-real gain from investments.

Leaving that aside, the company's operational profit fell 2.1% because it was unable to offset rising operational costs by raising fuel prices.

The government has a policy of keeping fuel prices low to control inflation.

The investment gain comes on the back of income earned from Petrobras's $70bn share offer last year.

An increase in the strength of the Brazilian currency, which lowers the value of debt held in weaker currencies, also contributed to the higher net profit.

Petrobras is carrying out a $225bn five-year investment plan to develop deepwater reserves.

It plans to become one of the world's biggest suppliers of oil.

Petrobras's chief financial officer Almir Barbassa told reporters: "Our financial results this year were extraordinarily better than last year, our debt ended up being smaller with the strengthening of the real."