Canadian timber exporter Canfor Corp is claiming at least US$250m in damages against the US over the imposition of countervailing and anti-dumping duties.

Notice of intent is to be filed under the North American Free Trade Agreement. Canfor accuses the US Commerce Department of violating several clauses of the agreement by imposing the anti-subsidy duty of 19.3% in August and an anti-dumping duty of 13% last week against Canadian softwood exports to the US.

Canfor chief executive David Emerson said the complaint would be valid even if the softwood dispute was settled because the company had suffered material damage to its business and reputation.