Attorney General Jeff Sessions on Monday announced new limits on an individual’s ability to seek asylum in the United States, a decision likely to affect thousands of Central American migrants fleeing violence and poverty in the hopes of gaining refuge.

The decision by Sessions comes after months of deliberation over whether victims of domestic violence and other private criminal activity — as opposed to state-sponsored crime — qualify to receive asylum. Thousands of asylum-seekers from El Salvador, Guatemala and Honduras have made such claims in recent years as they arrived at the U.S.-Mexico border.

Under the new policy, posted on the Justice Department’s website, Sessions said an asylum applicant “must show more than the [foreign] government’s difficulty” controlling private crimes, including that his or her home country condoned the private actions or demonstrated an inability to protect the victims.”

In general, Sessions wrote, “claims by aliens pertaining to domestic violence or gang violence perpetrated by non-governmental actors will not qualify for asylum.”

Speaking to an audience of immigration judges Monday morning, Sessions argued the United States cannot make individual asylum judgments based on unsafe conditions in a given country.

“We all know that many of those crossing our border illegally are leaving difficult and dangerous situations,” the attorney general said. “And we understand all are due proper respect and the proper legal process. But we cannot abandon legal discipline and sound legal concepts.”

Sessions said the decision would “restore sound principles of asylum and long-standing principles of immigration law.”

The Justice Department has struggled to reduce a backlog of more than 700,000 cases in the immigration court system, which has been flooded in recent years with claims by asylum-seekers from Central America. Sessions blamed the trend for swelling the case backlog and said the “vast majority” of current asylum claims are not valid.

Advocacy groups had already indicated they would oppose such a decision by Sessions.

“Gender-based violence is frequently perpetrated by private criminal actors whom governments are unable or unwilling to control,” the American Bar Association said in an April court filing. “Allowing gender-based violence as a ground for asylum … is critical to the advancement of human rights principles for women and girls, who will otherwise face life-threatening violence and abuse.”

The move is in line with others by Sessions aimed at reducing the immigration backlog. He recently announced new job performance metrics for immigration judges, which would require them to complete 700 cases each year. And in March he ruled that DOJ is not required to give every asylum-seeker a full hearing if they are unlikely to succeed after an initial review.

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