“We are reviewing our options, including legal action through the North American Free Trade Agreement (Nafta) and the World Trade Organization, and we will not delay in taking action,” they said.
Softwood lumber products, like pine, fir and spruce, are mainly used in the construction of single family houses.
The US has claimed for decades that Canada is unfairly subsidising its lumber industry by charging minimal fees to log public lands.
Commerce Secretary Wilbur Ross said in a statement that the US remains committed to “free, fair and reciprocal trade with Canada”, and that the decision is based on “a full and unbiased review of the facts in an open and transparent process”.
The department said it had determined that Canadian exporters have sold softwood lumber to the US at 3.2-8.89% less than fair value.