RIO DE JANEIRO, Nov 18 (Reuters) - A union representing workers in the Brazil's top oil region will vote on Thursday on a contract offer from state-run oil company Petrobras on Thursday or continue a strike, the most disruptive in 20 years, the union said Wednesday.
The union, Sindipetro Norte Fluminense, called the vote after Petroleo Brasileiro SA, as Petrobras is known, agreed to discuss its demand that members receive back pay for all the days they were on strike, not just half the days, as offered in a contract proposal last week.
SindeptroNF was one of only two locals that openly rejected calls last week from its national federation, FUP, to accept that contract, extending a nearly two-week strike to 17 days and counting.
The Petrobras offer includes a 9.53 percent wage increase and promises discussion of union demands to revive cut investments and block $15.1 billion of planned asset sales.
SindipetroNF represents workers on Petrobras' offshore platforms, support vessels and on-shore terminals in the Campos Basin, home to 64 percent of Brazil's oil output and 35 percent of its natural gas production. In terms of production it is the most important union local in the country.
So far, 10 of 17 FUP locals have voted to accept the contract and end the strike, but not all locals have voted.
Petrobras has said that the strike cut oil output in Brazil by about 100,000 barrels on Tuesday, or just under 5 percent of output, down from about 273,000 barrels a day shortly after the strike began Nov 1.
If the strike ends soon, Petrobras should be able to produce an average of 2.125 million barrels of oil in Brazil a day for all of 2015, an amount that would meet its goal of raising Brazil oil output by 4.5 percent, plus or minus one percentage point, analysts at Credit Suisse said in a note to clients on Wednesday. (Reporting by Jeb Blount; Additional reporting by Marta Nogueira; Editing by Steve Orlofsky)