Stephen Miller, a senior aide to U.S. President Donald Trump, spent months pushing for legislation that would give states the power to block children of undocumented immigrants from enrolling in public schools, Bloomberg reported Saturday.

The efforts are part of the Trump administration's immigration crackdown, which have sparked outrage amongst Democrats and immigration activists who have called the efforts cruel. The revelation comes a week after the administration adopted a new rule that would deny permanent resident status to immigrants deemed "likely" to use public services.

According to Bloomberg, the proposal was part of a slew of ideas that would allow the White House to act on immigration without congressional approval.

As far back as 2017, Miller pressed to find ways to limit undocumented immigrant's access to public services. That effort included the consideration of issuing a guidance memo from the Education Department (DOE), telling states that they had the option to refuse to allow undocumented students to attend public schools, Bloomberg reported.

“The memo wasn’t issued because the secretary would never consider it,” DOE spokesperson Liz Hill told Bloomberg.

The idea was ultimately abandoned because violates a 1982 Supreme Court decision that guaranteed access to public schools for all children. Plyer v. Doe prohibited states from denying free public education based on a child's immigration status.

Although this plan was never approved, Miller and Trump have already created policies that would deter immigrant children from attending school, including allowing Immigration and Customs Enforcement officers to arrest parents as they drop off their children, Vanity Fair reported.

Last week, the Trump administration announced that it was moving forward with one of its most aggressive steps yet to restrict legal immigration, denying green cards to many migrants who use Medicaid, food stamps, housing vouchers or other forms of public assistance.

Federal law already requires those seeking to become permanent residents and gain legal status to prove they will not be a burden to the U.S. — a "public charge," in government speak — but the new rules detail a broader range of programs that could disqualify them.

It's part of a dramatic overhaul of the nation's immigration system that the administration has been trying to put into place. While much of the attention has focused on Trump's efforts to crackdown on illegal immigration, the new change targets people who entered the United States legally and are seeking permanent status. It is part of an effort to move the U.S. to a system that focuses on immigrants' skills instead of emphasizing the reunification of families.