President Donald Trump’s administration has enacted a pause on all immigration applications filed by migrants from Latin America and Ukraine allowed into the U.S. under certain Biden-era programs, citing fraud and security concerns, according to two U.S. officials and an internal memo obtained by CBS News, the latter reports.

They include a policy, called Uniting for Ukraine, set up to offer a safe haven to those fleeing the war in Ukraine. Roughly 240,000 Ukrainians with American sponsors arrived in the U.S. under that process before President Trump took office.

The Trump administration had previously halted new entries under Biden-era parole policies. But in a memo dated February 14, Andrew Davidson, a top U.S. Citizenship and Immigration Services (USCIS) official, ordered an agency-wide "administrative pause" on all "pending benefit requests" filed by migrants already allowed into the U.S. under three Biden administration programs. These benefits would have allowed those arriving to stay in the U.S legally.

Because those allowed into the U.S. under these programs were only given temporary work permits and deportation protections that typically last for two years, many of them applied for other immigration benefits, lawyers and experts said.

The application freeze will remain in place indefinitely while government officials work to identify potential cases of fraud and enhance vetting procedures to mitigate concerns related to national security and public safety, according to the directive

"This effectively freezes their ability to move into another legal status," said Lynden Melded, who served as the top lawyer at USCIS during the administration of former President George W. Bush and now works as a partner at Berry Appleman & Leiden LLP. "In the interim, they would remain susceptible to removal from the country if the government terminates their parole status."