COLUMBUS — The possibility of one of the nation’s largest online charter schools shutting down halfway through the academic year is looming larger for its roughly 12,000 students and hundreds of employees as its sponsor moves to cut that tie, which could halt operations within a week.

Staff and students at the Electronic Classroom of Tomorrow knew before the sponsor’s decision Wednesday that ECOT might close mid-year, but for a different reason. The school had warned it could run out of money and be forced to close because of state efforts to recoup $60 million or more in disputed funding amid a related legal fight.

The sponsor, Educational Service Center of Lake Erie West, said its decision to suspend its arrangement with ECOT around the semester’s end next Thursday stemmed from the e-school’s financial troubles — specifically, that ECOT couldn’t afford to stay open for the rest of the school year or secure a required bond for its fiscal officer as of next month.

ECOT has until Wednesday to appeal the decision. The sponsor will work with the school and Ohio’s Department of Education “in the hopes of minimizing any negative impact these proceedings may have” on students, said Apryl Morin, who leads the sponsor’s Community Schools Center.

In Ohio, public charter schools can’t operate without a sponsor, the entity that establishes the school and also provides oversight and technical help.

A spokesman for ECOT said it tried unsuccessfully to work things out with the Department of Education during the past year and is working to avoid losing its sponsor.

“Our goal is to keep ECOT’s doors open and our students in the classroom and provide them with the education they deserve and the setting that is appropriate for their needs,” school spokesman Neil Clark said in an email.

The Ohio Department of Education said it’s ready to help the sponsor, students’ families and educators if ECOT’s operations are halted.

A shutdown next week would occur about a month before the Ohio Supreme Court is scheduled to hear arguments in ECOT’s case challenging how officials tallied student logins to determine that the virtual school was overpaid for the 2015-16 school year.

The state says that ECOT didn’t sufficiently document student participation to justify its funding and could owe millions more from 2016-17. ECOT alleges that officials wrongly changed criteria to adjust funding.