President Donald Trump's surprise tariffs on Mexico will have a "very bad" impact on the United States, Bill Richardson, former U.S. ambassador to the United Nations, told CNBC on Friday.
Trump blindsided the U.S.' neighbor to the south with the announcement Thursday night that his administration will impose a 5% duty on all Mexican imports starting June 10. The tariffs will increase gradually, to as much as 25% in October, the White House said.
"It's going to hurt our ranchers, our agriculture people, our farmers. It's going to be devastating," Richardson said on "Power Lunch."
"It's a wrong policy because it's based on the president's impulse," added Richardson, who is also a former governor of the border state of New Mexico.
Trump said he was imposing the tariffs to stop illegal immigrants from coming through Mexico into the U.S. The announcement came just as the approval process for the United States-Mexico-Canada Agreement, or USMCA, started to get underway.
If the tariffs are put in place, it would affect states across the U.S., which imported $346.5 billion in goods from Mexico last year, according to the Office of the U.S. Trade Representative.
The state that gets the highest share of imports from Mexico is Arizona, at 40%. About 38% of Michigan's imports and about 35% of Texas' imports come from Mexico.
Mexico hasn't announced any planned retaliation. On Friday, Mexican trade official Guillermo Malpica Soto told CNBC's "Closing Bell" his country won't retaliate until the threat seems more serious.
Richardson said he expects that will happen.
"Mexico is going to have to retaliate if we pursue this foolish policy," he said. "It's going to affect our economy. It's going to affect the border."
Plus, the duties put the USMCA in "real jeopardy," Richardson added. If tariffs are imposed, "why [are] Mexico and Canada and the U.S. Congress going to want to approve this?"
— CNBC's Jacob Pramuk contributed to this report.