The Trump administration is considering issuing sweeping travel restrictions for the citizens of dozens of countries as part of a new ban, according to sources familiar with the matter and an internal memo seen by Reuters.

Damir Ortiz, a 10-year-old with leukemia and a rare genetic disease that has caused a tumor in his left eye, was medevaced Wednesday from Cuba to the Nicklaus Children’s Hospital in Miami, after overcoming bureaucratic obstacles and the reluctance of the Cuban government.

Over 40 countries may face severe or total travel limitations by the United States, according to a memo obtained by the New York Times.