When the White House announced its new refugee policy Tuesday, administration officials said applicants from 11 nations are considered so high-risk that they will be subject to an additional 90-day freeze on potential admission to the United States.
But they refused to identify the 11 counties, citing "law enforcement sensitivities."
According to two government officials who were willing to identify the 11 nations to The Washington Post on condition of anonymity, they are Egypt, Iran, Libya, South Sudan, Yemen, Sudan, Iraq, Mali, North Korea, Somalia and Syria.
All are majority-Muslim except for South Sudan and North Korea.
Jonathan Hoffman, the chief spokesman for the Department of Homeland Security, said the purpose of the additional screening measures was to "raise the bar" for vetting refugee applicants.
The restrictions are consistent with other efforts by the White House to strictly limit the entry of foreign nationals from many majority Muslim countries, even though federal judges have blocked the administration's attempts to ban them outright.
Also notable is that the 11 nations include Egypt, a strategic U.S. ally, and Iraq, with which the United States has partnered to fight the Islamic State.
During the 90-day period, applicants from the 11 nations will be considered for admission only if doing so is in the United States' "national interest," officials said. The policy was announced Tuesday evening by executive order.
The two administration officials who confirmed the 11 nations' identities did so on condition of anonymity because the list is designated classified.
A blanket 120-day halt on refugee admissions expired Tuesday, so applicants from other countries will once more be admitted, albeit under more rigorous screening procedures, administration officials said. Those include enhanced background checks, biometric data collection and a potential review of applicants social media posts.
The United States will resume accepting refugees from the 11 countries deemed high risk following more detailed threat assessments, officials said.
Trump has cut the number of refugees eligible to be admitted by the United States over the next 12 months to 45,000, the lowest total since the Refuge Act of 1980.
"The United States will continue to resettle more refugees than any other country in the world, and we will continue to offer protection to the most vulnerable refugees while upholding the safety and security of the American people," the State Department said in a statement following the White House announcement.
Maria Sacchetti contributed to this report.