Trump Welcomes Mexico’s President in Surprisingly Warm Terms

But he also boasted about a falling rate of southern border crossings. Mr. López Obrador has played an important role in Mr. Trump’s relentless campaign to restrict immigration by ordering more vigorous enforcement on Mexican territory. “We’ve been helped greatly by Mexico on creating record numbers, in a positive sense, on our southern border,” Mr. Trump said.

The two leaders have little in common ideologically — Mr. López Obrador is an avowed leftist — but Mr. Trump has used the United States’ tremendous economic leverage, including threats of tariffs and even a total border closing, to pressure the Mexican leader.

Mr. López Obrador dismissed any notion of tension, telling Mr. Trump that “some people thought that our ideological differences would inevitably lead to confrontations.”

“Fortunately,” he continued, “this has not been the case.”

While few expected Mr. López Obrador to cross swords with his American counterpart, he was at times strikingly warm and congenial toward a president who, as a candidate, famously said that Mexico was “sending” criminals and rapists across the border into the United States.

Mr. López Obrador told Mr. Trump that “instead of aggression,” the U.S. president had granted Mexico “understanding and respect.” And he said Mr. Trump had “not tried to treat us as a colony; on the contrary, you have honored our condition as an independent nation.”

“That’s why I’m here to express to the people of the United States that their president has behaved with us with kindness and respect,” he added.

A Pew poll released in January found that 89 percent of Mexicans lacked confidence in Mr. Trump.

“The forecasts failed,” Mr. López Obrador told reporters at the end of the day. “We didn’t fight. We are friends, and we’re going to keep being friends.”