The Trump administration has declined to release nearly $7 billion in federal funding that helps pay for after-school and summer programs, support for students learning English, teacher training and other services.

The money was expected to be released by Tuesday. But in an email on Monday, the Education Department notified state education agencies that the money would not be available.

The administration offered little explanation, saying only that the funds were under review. It gave no timeline for when, or if, the money would be released, saying instead that it was “committed to ensuring taxpayer resources are spent in accordance with the president’s priorities.” The frozen funds are unrelated to the millions of dollars in cuts included in the domestic policy bill that squeaked through the Senate on Tuesday.

“It’s catastrophic,” said Jodi Grant, executive director of the Afterschool Alliance, a group that works to expand after-school services for students. She estimated that the federal dollars for after-school and summer-school programs — about $1.3 billion annually — support 1.4 million students, mostly lower income, representing about 20 percent of all students in after-school programs nationally.

The move is likely to be challenged in court and has already been criticized as illegal by Democrats and teachers’ unions, who emphasized that the money had been appropriated by Congress and was approved by President Trump in March as part of a broader funding bill.

“This is lawless,” said Randi Weingarten, president of the American Federation of Teachers.

The administration has taken an aggressive approach to cutting back the federal government’s role in education, including plans to eliminate the Education Department entirely. Though only Congress can abolish the department, the Trump administration has taken an ax to education staffing and funding more broadly as it seeks to whittle down the department.