LOS ANGELES — President Biden opened the three-day Summit of the Americas on Wednesday by promising leaders from Latin America that the United States was committed to helping the region combat crime, corruption and its economic struggles.
“These challenges affect all of us,” Mr. Biden told the leaders at the opening ceremony of the summit, a gathering of nations of the Western Hemisphere intended to address the region’s shared problems. “All of our nations have a responsibility to step up and ease the pressure people are feeling today.”
The United States is serving as the host to the ninth of these summits, which began in Miami in 1994. In brief remarks, Mr. Biden delivered a version of his domestic economic pitch, urging governments in the hemisphere to invest in workers and the middle class.
“What’s true in the United States is true in every country: Trickle-down economics does not work,” he said, prompting some applause from the audience inside the Microsoft Theater near the Los Angeles Convention Center.
“When we invest in strengthening workers and the middle class,” he said, “the poor have a ladder up, and those at the top do just fine. That’s how we can increase opportunity and decrease persistent inequity.”
Mr. Biden has hoped to use the summit to reassert U.S. leadership in the region and make diplomatic progress on a variety of fronts, but his efforts are already facing severe challenges.
His call to “get to work building the future this region deserves” was undercut days ago when several of the most prominent of its leaders declined to attend, citing the president’s refusal to invite the leaders of Cuba, Nicaragua and Venezuela.
But Mr. Biden proceeded on Wednesday night as if the snub had made no difference, saying that the gathering in Los Angeles would announce what he called “a groundbreaking, integrated new approach to managing migration and sharing responsibility across the hemisphere.”
White House officials have declined to offer specifics, but people familiar with the effort said that governments had been working on pledges for each to accept a certain number of refugees from the region.
Critics have questioned the value of such a declaration without the leaders of Mexico, Guatemala, Honduras and El Salvador — which generate almost 66 percent of the migration to the United States border every year — in attendance.
Administration officials said that those countries supported the effort, despite their absence. In his remarks, Mr. Biden said the declaration “represents a mutual commitment to invest in regional solutions that enhance stability, increase opportunities for safe and orderly migration.”
The leaders will begin formal meetings on Thursday.