WASHINGTON (Reuters) -Vice President Kamala Harris said on Wednesday she intends to visit Mexico and Guatemala soon as part of her plan to use diplomatic efforts to slow migration to the U.S.-Mexican border. President Joe Biden, who has moved away from his predecessor Donald Trump’s hardline immigration approach, gave Harris the job of leading U.S. efforts with Mexico and Central America’s Northern Triangle countries - Honduras, El Salvador and Guatemala - to stop migrants from crossing into the United States. Harris spoke to reporters on Wednesday while participating in a virtual roundtable with experts who offered recommendations on the region, focusing on the core causes of migration in the Northern Triangle. “Our focus is to deal with the root causes, and I am looking forward to traveling, hopefully as my first trip, to the Northern Triangle, stopping in Mexico and then going to Guatemala,” Harris said. Participants in the meeting included: Ambassador Nancy McEldowney, national security adviser to Harris; Andrew Selee, president of the Migration Policy Institute think tank; and Lisa Haugaard, co-director of the Latin America Working Group nonprofit advocacy group. The United States in March witnessed the most unaccompanied children attempting to cross the border since such record keeping began in 2010. Overall, more than 172,000 migrants were caught at the U.S.-Mexico border in March, according to an administration official. Of those, roughly 168,000 were picked up by border patrol agents between ports of entry - the highest monthly tally since March 2001. The United States must figure out how to bring about economic development in the Northern Triangle countries to curb immigration, Harris said. Most of the region’s people do not want to flee their homes but many do so because there are no opportunities to meet their needs, Harris added. Harris already has helped strike an agreement with Mexico, Honduras and Guatemala to temporarily surge security forces to their borders to help curb migrant flow. At a congressional hearing on Wednesday, Ricardo Zuniga, a U.S. special envoy to Central America, said the recent increase in migrant arrivals was part of a “recurring pattern” driven by crime and poor economic conditions in the Northern Triangle. Zuniga said the Biden administration is working to help social welfare agencies in the region to identify unaccompanied children traveling with U.S.-bound caravans and other groups to stop them from taking the “dangerous journey” north.