Brazil's state-led oil company Petrobras said on Thursday that it identified 28 areas where it believes it can cut costs in the wake of soaring investments and its first quarterly loss in 13 years.

The areas have been identified under the company's "Procop" cost-optimization program and s hould start showing results in January, the Rio de Janeiro-based company said in a Brazilian securities filing.

The plan is aimed at helping Petrobras Chief Executive Maria das Gra��as Foster find ways to revive stagnant production and help pay for a $237 billion five-year expansion plan, the world's largest corporate investment program.

Despite huge spending levels and the discovery of some of the world's largest offshore oil fields in the past five years, Petrobras has missed all its annual production targets for a decade and August oil and natural gas output fell to a 22-month low.

Procop will focus on areas that accounted for 63 billion reais ($31 billion) of spending in 2011, the so-called "manageable portion" of the company's 199 billion reais of outlays registered in Petrobras' accounts as cost of goods sold (COGS) and operational expenses.

The "manageable portion," which is subject to the direct control of executives, employees and contractors, represents just under a third of COGS and operational expenses.

The manageable portion excludes raw-material and fuels costs, royalties and other government shares of output, and spending on depreciation, depletion and amortization.

Fuel costs were one of the main drivers of Petrobras' 1.35 billion real ($665 million) second-quarter loss, the first in 13 years. Because the government has refused to let the company raise fuel prices in line with world prices, it has been selling gasoline and diesel fuel at a loss. The refining division alone lost 7 billion reais in the second quarter.

Manageable costs targeted under the plan include reduction of supplies on oil platforms and in producing oil fields as well as optimization of transportation, logistics and maintenance services in the exploration and production division.

In the refining and fuels transport division, Petrobras will seek to balance the level of production between refineries, reduce maintenance, pipeline, terminal and shipping costs and reduce stocks.

The gas and energy division will seek to cut the operational cost of its pipelines, to reduce the cost of supplies in thermal power and fertilizer plants as well as improve p l ant operations.

Improvements in parts purchases through standardization and simplification of standards and optimization of stocks are goals for general management.

The company's support division seeks to cut information technology, building maintenance and other costs.

($1 = 2.03 Brazilian reais) (Reporting By Jeb Blount)