The U.S. Department of Commerce says it is delaying its announcement on preliminary anti-dumping duties against Bombardier Inc. until Friday.
The company is expected to face additional export duties on its CSeries commercial jet.
The decision follows last week's move to impose nearly 220 per cent preliminary countervailing tariffs once deliveries to Delta Air Lines begin next year.
The Montreal-based transportation manufacturer has said it wouldn't be shocked if the U.S. piles on by announcing another "absurd" duty.
- 220% duty on CSeries jets: Boeing gets even more than it asked for in fight with Bombardier
- Bombardier calls 220% U.S. duty on CSeries planes 'absurd'
Colin Bole, Bombardier's sales chief for commercial aircraft, said the company expects the second duty to be a "significant number" but one that also makes no sense.
Boeing revised its request for anti-dumping duties to 143 per cent from around 80 per cent because of Bombardier's refusal to provide certain information to the Commerce Department.
The U.S. aerospace giant petitioned to the government in April after its smaller rival secured a deal for up to 125 of its CS100s with Delta in 2016.