United States President Donald Trump on Thursday said he will “permanently pause migration from all third-world countries”, a day after a suspected Afghan citizen shot two members of the National Guard in Washington DC.

In a social media post, Trump said that migration from third-world countries will be paused to “allow the US system to fully recover”, “terminate” millions of “illegal admissions” that he alleged his predecessor Joe Biden had allowed and “remove anyone who is not a net asset” to the nation, “or is incapable of loving our country”.

It was unclear how Trump would enforce the pause in migration. His previous actions to limit migration have been challenged in the courts.

The comments by Trump came hours after one of the two National Guard members, Sarah Beckstrom, succumbed to her injuries on Thursday. The second member is being treated in hospital.

The US immigration authorities on Wednesday paused the processing of all immigration requests from Afghan citizens after a man, Rahmanullah Lakanwal, who entered the country from Afghanistan in 2021, was identified as the suspect in the shooting.

Lakanwal was granted asylum in April under the Trump administration, Reuters reported.

He was among the tens of thousands of Afghans who arrived in the US under a programme named Operation Allies Welcome, which was launched by the Biden administration following the Taliban’s return to power in August 2021.

Many had worked with American forces and qualified for Special Immigrant Visas, though that programme had long suffered from severe backlogs.

On Thursday, the US president said that he will end all federal benefits and subsidies to non-citizens, denaturalise migrants “who undermine domestic tranquillity” and deport foreign citizens who are a security risk “or non-compatible with Western Civilization”.

The administration’s aim would be to achieve a major reduction in undocumented migrants and “disruptive populations”, Trump said. “Only reverse migration can fully cure this situation,” he added.

Trump, after assuming office for his second term in January, has effectively paused refugee admissions and tightened immigration regulations.

In some cases, the US government has used military aircraft to repatriate undocumented migrants, including Indians.