Brazilian state-controlled oil company Petrobras, which reported its worst quarterly loss in 13 years last week, said Monday it planned to achieve the production goals it set for 2012.

The loss was the result of a combination of factors that are unlikely to repeat themselves, Petrobras said.

The company will recover in the second half of the year and meet its goal of finishing 2012 with domestic output of 2.1 million barrels per day (bpd), Petrobras CEO Maria das Graças Foster said during a conference call with investors.

Last Friday, Petrobras reported a net loss of 1.35 billion reais (some $633 million at the current exchange rate) in the second quarter, attributing the result to the depreciation of the real relative to the dollar.

That compared with net income of 9.21 billion reais in the first quarter of this year and 10.94 billion reais (then equivalent to $6.86 billion) in the second quarter of 2011.

Petrobras shares fell up to 6 percent in trading on Monday, dragging down the Sao Paulo Stock Exchange on a day when international markets trended higher.

"These losses were the result of a combination of factors that we will be unlikely to see again, especially with the same magnitude as they had in the second quarter," Foster said.

The CEO said she was "confident and convinced" that Petrobras would meet "the results expected over the next quarters."

Petrobras set the goal of increasing production in Brazil from 2.02 million bpd in 2011 to 2.1 million bpd this year and 2.5 million bpd in 2016.

Total production, including fields abroad, totaled 2.58 million bpd, down 4 percent from the level in the first quarter.

According to Petrobras, the depreciation of the real, down 8.53 percent relative to the greenback thus far this year, "significantly affected the financial result" because of the company's dollar-denominated debt and the operational costs the company must incur in the U.S. currency.

Petrobras also attributed the net loss to other factors, including a drop in crude production due to maintenance work at wells and the sharp gap between the price it charged for fuel at the pump in Brazil and the price the company paid for fuel imports.

Lower international fuel prices at the end of the second quarter also reduced the value of Petrobras' inventories at its foreign refineries, the company said.

Brazil had to increase its imports of liquefied natural gas from 1.6 million cubic meters per day in the second quarter of 2011 to 9 million cubic meters per day in the second quarter of this year to meet demand from power plants. EFE