With just a week to go until U.S. President Donald Trump's threatened date for boosting tariffs on some Canadian exports to 35 per cent, Canada's top trade negotiators are downplaying the likelihood of reaching a deal by that deadline.

His warning follows signals from Prime Minister Mark Carney that the two sides may not be able to reach an agreement by a self-imposed deadline of Aug. 1

The agreements have been overshadowed by U.S. firms' warnings that the tariffs will affect their bottom lines and prolong uncertainty in the economy.