US manufacturers said the tariff, set to take effect June 10, would have devastating consequences on them and American consumers. US stocks tumbled on Wall Street in response to Trump's planned action.

"Imposing tariffs on goods from Mexico is exactly the wrong move," said Neil Bradley, executive vice president of the US Chamber of Commerce, which is exploring legal action in response to the tariffs. "These tariffs will be paid by American families and businesses without doing a thing to solve the very real problems at the border. Instead, Congress and the president need to work together to address the serious problems at the border."

Mexican President Andres Manuel Lopez Obrador dispatched his foreign secretary to Washington to try to negotiate a solution. He said social problems are not solved with coercive measures, but also seemed convinced that Trump just needed to be informed about all the steps Mexico has taken to slow illegal migration.

Mexico has stepped up raids on migrant caravans travelling through the southern states of Chiapas and Oaxaca this year. It has deported thousands of migrants and frustrated thousands more who wait endlessly for permits that would allow them to travel legally through Mexico.

US Secretary of State Mike Pompeo spoke with his Mexican counterpart via telephone Friday, said State Department spokeswoman Morgan Ortagus, who's travelling with Pompeo in Bern, Switzerland. Ortagus said the department doesn't comment on details of diplomatic conversations.

"We maintain an ongoing dialogue and close cooperation with Mexico on a wide range of issues, including border security efforts," she said. "The United States and Mexico recognise that managing our shared border is a challenge common to both countries."

Administration officials told reporters in a briefing call Thursday evening that Mexico could prevent the tariffs from kicking in by securing its southern border with Guatemala, cracking down on criminal smuggling organisations, and entering into a "safe third country agreement" that would make it difficult for those who enter Mexico from other countries to claim asylum in the US

"We fully believe they have the ability to stop people coming in from their southern border and if they're able to do that, these tariffs will either not go into place or will be removed after they go into place," said acting White House chief of staff Mick Mulvaney.

Trump said the percentage will gradually increase - up to 25% - until the migration problem is remedied.

"Mexico has taken advantage of the United States for decades," Trump said in a tweet Friday. "Because of the Dems, our Immigration Laws are BAD. Mexico makes a FORTUNE from the US, have for decades, they can easily fix this problem. Time for them to finally do what must be done!"

Trump's decision showed the administration going to new lengths, and looking for new levers, to pressure Mexico to take action - even if those risk upending other policy priorities, like the United States-Mexico-Canada Agreement, a trade deal that is the cornerstone of Trump's legislative agenda and seen as beneficial to his reelection effort.

Keeping the economy rolling also is critical to Trump's reelection, and business was not happy with the president's planned tariff on Mexican imports.

The stock market's tumble on Friday all but guarantees that May will be the first monthly loss for the market in 2019. The news hit automakers particularly hard. Many of them import vehicles into the US from Mexico.

Some of Trump's fellow Republicans in Congress opposed the tariff. Republican senators have made almost weekly treks to the White House to nudge the president off his trade wars, and this latest move sent them scrambling again to signal their displeasure in hopes of reversing Trump's actions.

Australian Associated Press