A $30 billion settlement between Visa Inc., Mastercard Inc. and retailers to cap credit-card swipe fees is likely to be rejected by a federal judge in Brooklyn, a setback in the two decade-long litigation.

Judge Margo Brodie of the US District Court of the Eastern District of New York indicated in a hearing Thursday that she probably won’t approve the deal, according to court records. Brodie hasn’t officially ruled, but said she would “issue a written decision” in coming days, according to a summary of her comments in court on Thursday.

Retailers have fought for decades to slash their share of the cost for accepting card payments, also known as interchange fees. Much of those fees are passed on to the banks that issue the cards, including giants like JPMorgan Chase & Co. and Citigroup Inc.

The deal, which was announced in March and subject to court approval, would have let merchants charge consumers extra in transactions involving Visa or Mastercard credit cards. When the agreement was unveiled, the parties said it also would have allowed the use of pricing tactics to steer consumers to lower-cost cards.

“The court’s comments strongly suggest that she won’t accept the settlement,” said Justin Teresi, a Bloomberg Intelligence analyst. “While Judge Brodie doesn’t seem convinced that larger retailers should be allowed to opt out from the settlement, provisions like changes to digital wallet acceptance rules and some state bans on surcharges likely present real adequacy issues.”

Spokespeople for both Visa and Mastercard said the firms were “disappointed” by the developments.

“We believe the settlement presented a fair resolution of this long-standing dispute, most notably by giving business owners more flexibility in how they manage their card acceptance activities,” a representative for Mastercard said in a statement. “We will pursue our options to ensure a proper resolution of this matter.”

Visa’s spokesperson said that “continued engagement between industry and the merchants is the best way forward.”

Read More: Visa, Mastercard Reach $30 Billion Deal With US Retailers

Swipe fees totaled more than $172 billion last year, according to the Merchants Payments Coalition. Reactions were mixed when the settlement was announced in March, with some coalitions of retailers pledging to take a close look and some quickly opposing it.

Visa shares slipped less than 0.7% in early trading in New York, while Mastercard’s stock was little changed. Both companies’ shares have underperformed the S&P 500 Financials Index so far this year.

“It seems that the judge has yet to make a final decision, but if the settlement is rejected, it may force the parties to go back to the drawing board and elongate a final settlement,” Sanjay Sakhrani, an analyst at Keefe, Bruyette & Woods, said in a note to clients. “The most obvious assumption would be that the judge doesn’t think this settlement is adequate.”

The Retail Industry Leaders Association, which represents large merchants including Target Corp. and Home Depot Inc., called the settlement a “mere drop in the bucket” at the time and said its terms need “to be carefully reviewed” to see if they remedy the harm done.

On Thursday, another group praised the judge’s remarks.

“We’re gratified to see that the court recognized how bad this settlement was,” said Doug Kantor, general counsel for the National Association of Convenience Stores.