Navarro and Ross, who have advocated stronger trade policies to reduce U.S. trade imbalances, went on Sunday U.S. television news shows to try to contain the global fallout from Trump's announcement.
Trump said the US will set the tariffs at 25% for steel and 10% for aluminum last Thursday, causing concerns about higher prices for American consumers as well as the potential threat of retaliation from other countries.
Commerce Secretary Wilbur Ross on Sunday said the impact of President Donald Trump's recently announced tariffs on imported steel and aluminum would be minor when it comes to some of America's favorite products: beer and cars.
In a subsequent interview on NBC's "Meet the Press", Ross allowed for the possibility that Trump may yet change his mind, as he has on other issues.
Ross said there was no indication yet that Trump would consider exemptions for countries, but he did not rule it out.
"We shall see, we shall see".
"Using "national security" tools to implement tariffs could embolden other countries to impose "national security" tariffs on US exporters or otherwise restrict USA goods and services sold to their markets", Business Roundtable President and CEO Joshua Bolten said in a statement on Thursday. They have been talking with me. "So, we'll have to see the intricate details, but that certainly is the broad outline and therefore it will have a fairly broad effect", he said. Attention now falls on what his final decision on the tariffs is going to look like.
Peter Navarro, director of the White House National Trade Council, said countries will not be excluded from the tariffs because that would become a slippery slope, but there will be a mechanism for corporate exemptions in some cases.
"There will be an exemption procedure for particular cases where we need to have exemptions, so that business can move forward", Mr Navarro said on CNN's State of the Union program. "But at this point in time there will be no country exclusions", Navarro said, without elaborating.
"As soon as you start exempting countries you have to raise the tariffs on everybody else".
Ross argued on ABC that while any retaliation might affect an individual producer for "a little while", it won't amount to more than a "rounding error" for the economy.
Josh Bolten, chief executive officer of the influential Business Roundtable and former chief of staff to President George W. Bush, described the tariffs as "a huge mistake" on the "Fox News Sunday" program.
Energy industry officials raised concerns about the tariffs on steel since the sector relies on imports. Our Steel and Aluminum industries are dead.
Ross said the White House did not plan to grant exemptions for US allies such as Canada, which is expected to take the biggest hit from the tariffs because it exports the most steel and aluminum to the United States.
"You're letting China off the hook".