A top United Nations official has criticized the United States' deportation of migrants from its southern border, pushing Washington for faster action to roll back hardline immigration policies left over from the previous administration.

Iran PressAmerica: Filippo Grandi, UN High Commissioner for Refugees (UNHCR), urged the US administration to do more, work faster and more strategically with Mexico and Central America to offer alternatives to illegal migration by improving security and job opportunities.

"We hear a lot of these programs being talked about, but we see very little at this moment still happening on the ground. And I think that this is the real issue ...to prevent these movements from happening again or rather from continuing to happen," Grandi, previously Commissioner-General of the UN Agency for Palestine refugees, told Reuters. His trip also included Mexico and El Salvador.

US President Joe Biden vowed to lift many of the strict immigration policies of his predecessor Donald Trump. Still, several of Trump's most criticized measures remain in place, including the Migrant Protection Protocols (MPP) program, informally called "Remain in Mexico", and Title 42, which enables quick deportations of migrations due to the COVID-19 pandemic.

"The US is now deporting them back very quickly, but we disagree with that," Grandi said.

"I am worried that the political context is very strong and for this administration, it may be difficult to do the right thing, which they want to do," he said, adding that the United States should ensure "due process" before deportations.

The United States has deported more than 1.2 million migrants since the start of the pandemic, according to the American Immigration Council. Detentions at the US-Mexico border have hit record highs.

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