* Company plans to cut investment 30 percent, Globo says
* Writedown related to construction of five refineries
RIO DE JANEIRO, Jan 22 (Reuters) - Brazilian state-run oil company Petrobras will take a charge of about 10 billion reais ($3.9 billion) in its delayed third-quarter results to write down overvalued assets, the O Globo newspaper reported on Thursday, citing an unnamed government source.
Petroleo Brasileiro SA, as Petrobras is formally known, also plans to cut investment by 30 percent as part of a plan to preserve cash as a contract-fixing, bribery and political kickback scandal cuts it out of financial markets and falling oil prices crimp revenue, the paper said.
Petrobras had committed itself to investing an average of $44 billion a year under its $221 billion investment plan for 2014-2018 announced last year, but it warned in December that it would cut spending..
The company will write down the value of five refineries and two natural gas pipelines, the paper said.
Petrobras did not immediately respond to requests for comment on the story.
The results, originally scheduled for release in November, were delayed after a probe of corruption at Petrobras led auditor PricewaterhouseCoopers to refuse to certify the company's accounts. The company's board will meet on Jan. 27 to discuss and approve third-quarter financial data, Globo said.
Police, prosecutors and suspects arrested in the case said Petrobras executives conspired with construction and engineering companies to inflate the value of contracts for refineries, ships and other goods and services.
They said some of the excess charges were then kicked back to executives, politicians and political parties as bribes and campaign contributions.
Reuters reported on Jan. 6 that Petrobras' third-quarter results were likely to reflect the full amount of write-downs from the scandal.
About 40 have been arrested in the case, including three former Petrobras senior executives and senior executives of some of Brazil's largest construction and engineering companies.
$1 = 2.5789 Brazilian reais Reporting by Jeb Blount; Editing by Guillermo Parra-Bernal