WASHINGTON, March 9 (Reuters) – U.S. President Donald Trump could exempt more countries from trade tariffs, U.S. Treasury Secretary Steven Mnuchin said on Friday. Trump signed an order for 25 percent tariffs on steel imports and 10 percent for aluminum at the White House on Thursday, but exempted Canada and Mexico. “The president can do exemptions and my expectation is there may be some other countries that he considers in the next two weeks,” Mnuchin said in an interview with broadcaster CNBC. Mnuchin added that exemptions for specific products would be decided by Commerce Secretary Wilbur Ross. “He will be publishing regulations very quickly on how those products could be exempt,” Mnuchin said.