A widely followed former American diplomat questioned on Friday whether President Donald Trump was adopting the right strategy by threatening Mexico with a new tariff because of immigration issues.

Trump announced Thursday that his country plans to impose a 5% tariff on all Mexican imports from June 10. In a statement, he attributed that unexpected move to a "border crisis" that has resulted in America being "invaded by hundreds of thousands of people." He even suggested that he could raise the tariff on Mexico's goods to 25% by Oct. 1 this year if the country did not sufficiently halt the flow of migrants into the U.S.

Speaking with CNBC's "Street Signs" on Thursday evening U.S. time, John Negroponte questioned whether Trump's move would have the desired effect.

"I think it's both bad politically and bad economically and I don't think it's really going to help solve the immigration problem, either, which is what Mr. Trump said he's trying to attack," said Negroponte, current vice chairman of consultancy McLarty Associates and formerly U.S. ambassador to Honduras, Mexico, the Philippines, the United Nations, and Iraq.