BOSTON — A coalition of U.S. colleges and universities is urging Congress to pass a new coronavirus relief bill with at least $120 billion for higher education, saying the sector faces a crisis of “almost unimaginable” scale.

The letter signed by the American Council on Education and 100 other groups says financial losses caused by the pandemic are far worse than schools had expected. Colleges have laid off thousands of workers to cut costs, but the letter says the pared-down operations will unstainable without additional federal help.

Colleges have had to increase financial aid to help students who are struggling to pay tuition, and schools have lost revenue from closed dorms and dining halls.

Enrollments have also decreased amid the pandemic, with a 13% drop in freshmen across all U.S. institutions. At the same time, many states have cut their higher education budgets.