MIAMI (AP) — The NCAA is preparing to delay a potential landmark vote on legislation that would permit college athletes to be compensated for their fame for the first time after receiving a warning from the Department of Justice about potential antitrust violations.

NCAA President Mark Emmert on Saturday emailed a letter to Makan Delrahim, assistant attorney general of the DOJ’s antitrust division. The letter was obtained by The Associated Press.

In the letter, Emmert said he strongly recommended putting off votes on new name, image and likeness rules by the two key NCAA legislative bodies that had been scheduled for next week.

“The NCAA and its member schools are committed to ensuring that NCAA rules comply with all applicable laws, including federal antitrust law,” Emmert wrote. “We believe, as courts have regularly held, that our current amateurism and other rules are indeed fully compliant. Whenever we consider revisions to the rules, however, we of course receive input from many interested parties, and we welcome your invitation to consult with the Department so that we can hear and fully understand its views as well.”

The New York Times was first to report Emmert’s letter to the Department of Justice.

USA Today reported Friday that Delrahim had sent a letter to Emmert, expressing concerns about the NCAA’s NIL proposal and the restrictions it put on athletes’ ability to access the free market.

The NCAA Division I Council is scheduled Monday to consider proposed legislation that would allow athletes to strike financial deals with third parties to endorse or sponsor products or events, make personal appearance or be an online influencer. Schools would not be involve in the compensation.

The NIL reform has been in the NCAA’s legislative pipeline for more than year. The urgency to make changes increased as state legislatures across the country followed the lead of California and worked to pass bills that would override the NCAA’s rules banning college athletes from cashing in on their fame.

Six states have passed bills and Florida’s is scheduled to be the first to go into effect in July.

College sports officials have argued that it would be impossible to manage a national organization if different states have different rules. While working on its own solution, the NCAA has also turned to Congress for help in the form of federal legislation that will usurp state laws and also provide protection from further legal challenges to the NCAA’s NIL rules.

While both Republicans and Democrats in Washington have already put forth bills, the two sides have different ideas on the best way to proceed. The Republican bills are seen as more NCAA friendly and limited while the Democrats are looking to make more sweeping changes to college athletics.

Adding to the uncertainty, the Supreme Court has agreed to review a court decision in an antitrust lawsuit — the so-called Alston case — the NCAA has said blurred “the line between student-athletes and professionals” by removing caps on compensation that major college football and basketball players can receive.

The high court will hear the case later this year.

There had been momentum for delaying next week’s vote even before the DOJ’s letter because of all the uncertainty. Now the potentially historic change to NCAA rules appears to be heading for indefinite hold.