Cindy Saine at the State Department contributed to this report.
The United States and Mexico have reached a deal on migration to avert tariffs, but U.S. officials say President Donald Trump retains the authority to impose tariffs if Mexico fails to live up to it.
"I am pleased to inform you that The United States of America has reached a signed agreement with Mexico. The Tariffs scheduled to be implemented by the U.S. on Monday, against Mexico, are hereby indefinitely suspended," Trump said Friday on Twitter.
"Mexico, in turn, has agreed to take strong measures to stem the tide of Migration through Mexico, and to our Southern Border. This is being done to greatly reduce, or eliminate, Illegal Immigration coming from Mexico and into the United States," Trump said.
Speaking on the sidelines of the G-20 finance ministers meeting in Japan, U.S. Treasury Secretary Steven Mnuchin told the Reuters news agency Saturday that the deal met Trump's objectives of fixing immigration problems on the southern U.S. border, but that tariffs could be imposed if Mexico did not meet U.S. expectations.
"Our expectation is that Mexico will do what they've committed to do and our expectation is that we won't need to put tariffs in place, but obviously if that's not the case, the president retains that authority."
After Mnuchin's cautionary remarks, Trump sounded a note of optimism early Saturday, tweeting that "Mexico will try very hard, and if they do that, this will be a very successful agreement for both the United States and Mexico!"
Mexican President Andres Manuel Lopez Obrador said on Saturday that he had spoken with Trump, offering him friendly ties and a commitment to dialogue.
"I told [Trump] that in Tijuana I will not raise a closed fist, but an open and frank hand," the Mexican president said in a post on Twitter.
U.S. and Mexican officials returned to the negotiating table Friday for a third day of talks to find a way to stem the flow of Central American migrants across the U.S. southern border that had threatened trade between the neighboring countries.
Trump's trade wars with Mexico and other countries appear to have spooked American companies into putting the brakes on hiring, as they added just 75,000 jobs in May, far fewer than the 180,000 economists expected, the Labor Department reported Friday.