US Vice President Kamala Harris on Monday said the US hoped to work with Guatemala to address the causes of illegal migration by bringing "a sense of hope" to a country plagued by poverty and violence.
Ms Harris, on her first trip abroad since taking office, met President Alejandro Giammattei in Guatemala City.
She said reducing undocumented migration from Central to North America was a priority for US President Joe Biden's administration.
"Most people do not want to leave the place where they grew up", loved ones and people with whom they share a language and culture, Ms Harris said.
But they often did so "either because they are fleeing some harm or because they simply cannot satisfy their basic needs by staying at home", she said.
Regardless of their reasons, Ms Harris urged would-be migrants not to make the journey.
"Do not come," she said. "The United States will continue to enforce our laws and secure our borders.
"If you come to our border, you will be turned back."
Instead, she proposed that the US and Guatemala work together to find solutions to long-standing problems.
People must be given "a sense of hope that help is on the way", Ms Harris said.
"It must be coupled with relationships of trust. It must be coupled with tangible outcomes, in terms of what we do as leaders to convince people that there is a reason to be hopeful about their future and the future of their children."
Mr Giammattei said Guatemala wanted to co-operate "to create conditions in Guatemala so that [young people] can find here the hope they do not have today".
Ms Harris announced a joint task force on smuggling and human trafficking, a women's empowerment programme, and an anti-corruption task force to help Central American law enforcement.
She rejected Republican criticism that neither she nor Mr Biden had visited the US southern border, saying she had gone to Central America to discuss matters in a "way that is significant and has real results" rather than making "grand gestures".
Ms Harris, scheduled to meet Mexican President Andres Manuel Lopez Obrador on Tuesday, said she told Mr Giammattei the US would send 500,000 doses of coronavirus vaccines to Guatemala.
Her trip is part of the Biden administration's promise to enact a more humane immigration policy after the hardline approach taken by former president Donald Trump.
But the Republican opposition accused Mr Biden of creating a crisis on the country's southern border by failing to rein in migration.
Congress must still decide whether to approve the $861 million Mr Biden has asked for next year as part of a $4 billion plan to tackle the problem.
US officials have recently called on Central American countries to defend democracy and fight corruption to improve conditions at home and eliminate a driving factor for migration.
Mr Giammattei was assertive about his country's anti-corruption stance.
"How many cases of corruption have I been accused of? I can give you the answer: zero."