Commerce Secretary Wilbur Ross says the White House is seeking to take a "surgical approach" to new tariffs, saying it is possible Canada and Mexico could be exempted.

House Speaker Paul Ryan used the same language Tuesday in calling for President Donald Trump to use a more targeted "surgical approach" to avert a potentially dangerous trade war.

Ross told reporters Wednesday, "The president indicated that if we can work something out with Canada and Mexico they will be exempted."

He said it's "not inconceivable that others could be exempted on a similar basis."

Trump plans to impose a 25 percent tariff on steel imports and a 10 percent tariff on aluminum imports. But he has held out the possibility that Canada and Mexico might not face tariffs if they are willing to offer more favorable terms under the North American Free Agreement (NAFTA), which is being renegotiated.

Earlier Wednesday, Ross defended the tariffs saying the United States is not seeking a trade war and the decision to impose steep tariffs on steel and aluminum imports was "thought through."

"We're not looking for a trade war," Ross told the CNBC cable network, speaking a day after Trump's top economic adviser Gary Cohn resigned in apparent protest over the controversial tariffs.

"We're going to have sensible relations with our allies," he added, arguing that a jump in steel prices could be avoided with increased domestic production of the commodity.

Ross played down the Cohn resignation, insisting "this is not some sort of a palace coup." He said the departing economic adviser "has been contemplating some sort of a move for some little while."

The 57-year-old former Goldman Sachs executive lobbied passionately against the tariffs, but lost out to a decidedly more protectionist team that included Ross and White House trade adviser Peter Navarro.

"This is not going to be a big trade war," Ross said Wednesday. "The president would not have indicated flexibility on Canada and Mexico if he just wanted to do very extreme things.

"This is an idea that's been thought through over time."

Trump said Canada and Mexico could be exempted from steel and aluminum tariffs if they showed greater willingness to revamp (NAFTA) to address U.S. interests.

Shortly after Ross delivered his comments U.S. foreign trade figures for the month of January showed a widening of the trade deficit, which reached its highest level in nine years at $56.6 billion in one month.

Trump took to Twitter Wednesday to emphasize that the annual US trade deficit had reached $800 billion last year -- which he blamed on "bad policies & leadership" from his White House predecessors.

This report contains material from The Associated Press and AFP was used in this report.