"From now on, an alien who is in the U.S. temporarily and wants a Green Card must return to their home country to apply, except in extraordinary circumstances," the US Citizenship and Immigration Services (USCIS) said in a statement on Friday.
So far, it was possible for foreign nationals, including tourists, students and others, to apply for a Green Card while in the US under certain conditions.
More than half of the Green Cards issued each year are granted under this procedure, according to the Washington Post.
Among others, one of the requirements is that the applicant did not intend to stay for a prolonged period from the outset.
"Nonimmigrants, like students, temporary workers, or people on tourist visas, come to the U.S. for a short time and for a specific purpose," USCIS said.
"Our system is designed for them to leave when their visit is over. Their visit should not function as the first step in the Green Card process."
The rule change would help free up "limited USCIS resources to focus on processing other cases [...], including visas for victims of violent crime and human trafficking, naturalization applications, and other priorities."
Since US President Donald Trump took office for a second term last year, Washington has tightened its migration and border policy, with the most drastic measures, such as entry bans and bail requirements, primarily directed at citizens from the Middle East or Africa.
