A federal judge has blocked JetBlue Airways’ acquisition of Spirit Airlines following a lawsuit by the Justice Department (DOJ) claiming the deal would be anti-competitive and harm consumers.

The proposed $3.8 billion merger aimed to create the fifth-largest airline in the U.S., but the DOJ argued that it would lead to increased fares for price-sensitive consumers by eliminating the discount carrier from the market. The judge ruled in favour of the DOJ, stating that JetBlue’s conversion of Spirit’s planes to its layout and higher average fares would negatively impact cost-conscious travellers who rely on Spirit’s low fares.

Both JetBlue and Spirit expressed disagreement with the ruling and are evaluating the next steps. Spirit’s shares dropped significantly after the decision, while JetBlue’s stock saw a modest gain. The DOJ, pleased with the ruling, emphasised its commitment to enforcing antitrust laws to protect consumers.