RIO DE JANEIRO (Reuters) - Brazil state-run oil company Petrobras (PETR4.SA: Quote, Profile, Research) (PBR.N: Quote, Profile, Research) said on Monday a strike started by its workers at midnight would cut its production by only 136,000 barrels per day.

Earlier on Monday, the company said output was expected to fall by 300,000 bpd, or 16 percent of its total output, which accounts for most of Brazil's oil and gas production. Brazil puts out roughly 1.8 million bpd of oil and gas.

Oil workers started a five-day strike on Monday in the Campos Basin, which produces about 80 percent of Brazil's crude, over demands that days used for traveling from platforms to shore be counted as work days.

(Reporting by Denise Luna; writing by Reese Ewing)