(Adds Petrobras comment, 2nd pararaph))
BRASILIA, March 17 (Reuters) - Brazil's state-run oil producer Petroleo Brasileiro SA plans to cut 15 percent of its staff through a voluntary layoff program to be announced by mid-year, newspaper o Estado de S.Paulo reported on Thursday.
Petrobras' press office said no decision has been taken on a voluntary layoff program. "Petrobras assesses its policies and labor programs in a regular basis," the company said in an emailed statement in response to a query on the Estado newspaper report.
According to Estado, Petrobras, at the epicenter of a massive corruption investigation roiling Brazil's politics, expects to lay off up to 12,000 workers with the program as part of efforts to reduce costs. The report cited sources familiar with the company's plans.
Estado said the sources expect the voluntary layoff program to be announced along with the company's business plan for 2016-2020,
Earlier this month, two sources told Reuters that Petrobras would cut capital spending by one-fifth in the period.
There has been a dramatic downturn in Petrobras' prospects since it discovered some of the largest-ever offshore oil resources a decade ago. A widespread price-fixing and political kickback scandal has driven up costs and delayed projects. (Reporting by Silvio Cascione; Editing by Bernadette Baum and W Simon)