Low-cost air carriers JetBlue Airways and Spirit Airlines canceled their $3.8 billion merger agreement on March 4, after a U.S. judge blocked the deal in January on anti-competition concerns.

According to The Guardian, a successful deal would have created the fifth-largest carrier in the United States and helped Spirit ensure its survival. But William Young, the U.S. district judge in Boston ruled the deal would harm consumers by reducing competition.

“With the ruling from the federal court and the Department of Justice’s continued opposition, the probability of getting the green light to move forward with the merger anytime soon is extremely low,” JetBlue’s CEO, Joanna Geraghty, told employees in an internal note seen by Reuters.

“Even if the ruling was overturned on appeal, we simply don’t see a path to regulatory approval by the required July 24 deadline.”