WASHINGTON, United States (AFP)— President Donald Trump has halted arrivals of refugees already cleared to enter the United States, according to a memo seen Wednesday, as he quickly pursues a sweeping crackdown on migration.

Following an executive order signed Monday hours after Trump took office, “all previously scheduled travel of refugees to the United States is being cancelled,” said a State Department email to groups working with new arrivals.

The memo asked the UN International Organization for Migration not to move refugees to transit centres and said that all processing on cases has also been suspended.

Refugees already resettled in the United States will continue to receive services as planned, it said.

Trump in each of his presidential campaigns has run on promises to crack down on undocumented immigration.

But the refugee move also targets a legal pathway for people fleeing wars, persecution or disasters.

In his executive order, he said he was suspending refugee admissions as of January 27 and ordered a report on how to change the program, in part by giving “greater involvement” to states and local jurisdictions, which he said were being “inundated.”

It also revoked his predecessor Joe Biden’s decision to consider the impact of climate change in refugee admissions.

Trump said during his election campaign that immigrants were “poisoning the blood of our country” and earlier rose to prominence questioning the citizenship of Barack Obama, the first African-American president.

New Secretary of State Marco Rubio, the son of Cuban immigrants, said Wednesday that the State Department will “no longer undertake any activities that facilitate or encourage mass migration. ”

“Our diplomatic relations with other countries, particularly in the Western Hemisphere, will prioritise securing America’s borders, stopping illegal and destabilising migration and negotiating the repatriation of illegal immigrants,” Rubio said in a statement.

Biden had embraced the refugee program as a way to support people in need through legal means.

In the 2024 fiscal year, more than 100,000 refugees resettled in the United States, the most in three decades.

The Democratic Republic of Congo and Myanmar have been among the top sources of refugees in recent years.

Senator Jeanne Shaheen, the top Democrat on the Senate Foreign Relations Committee, voiced alarm at Trump’s moves and said that acceptance of refugees was “a core American value.”

“The US Refugee Admissions Program has a long history of bipartisan support and is a life-saving tool for the most vulnerable refugees, all while making Americans safer by promoting stability around the world,” she said.

The State Department memo said that Afghans who worked with the United States until the collapse of the Western-backed government in 2021 could still arrive through their separate resettlement program.

But Shaheen voiced concern that Afghans were also being left in limbo with flights cancelled.

The UN high commissioner for refugees estimates that there are 37.9 million refugees in the world, among some 122.6 million displaced people.

Krish O’Mara Vignarajah, president and chief executive officer (CEO) of Global Refuge, which advocates for refugees, said that Trump’s decision was “devastating” to people who had already lost so much.

“Refugees go through one of the most rigorous vetting processes in the world, and it’s heartbreaking to see their dreams of safety derailed just days before, or in some cases, just hours before they were set to begin their new lives here,” she said.