The United Steelworkers Union is calling for a strike at nine refineries mostly in Texas and California after it says negotiations with Shell Oil Company broke down less than two weeks after they began.
The union asked about 3,800 workers at the refineries to strike shortly early Sunday morning, following the expiration of their contract.
Negotiations over a new contract had started Jan. 21. The union says Shell representatives left the bargaining table after United Steelworkers rejected an offer from the company.
Shell officials did not immediately return a call from The Associated Press seeking comment.
Shell is serving as the lead company in national oil bargaining talks with the union.
United Steelworkers represents about 30,000 workers at refineries, terminals, petrochemical plans and pipelines across the country.