A fed­er­al judge is sid­ing with the Biden ad­min­is­tra­tion and block­ing Jet­Blue Air­ways from buy­ing Spir­it Air­lines, say­ing the $3.8 bil­lion deal would re­duce com­pe­ti­tion.

The Jus­tice De­part­ment sued to block the merg­er, say­ing it would dri­ve up fares by elim­i­nat­ing Spir­it, the na­tion’s biggest low-cost air­line.

Jet­Blue said it dis­agreed with the rul­ing and was con­sid­er­ing whether to ap­peal.

The New York car­ri­er ar­gued that it needs the deal to com­pete bet­ter against big­ger ri­vals that dom­i­nate the U.S. air-trav­el mar­ket.

“We con­tin­ue to be­lieve that our com­bi­na­tion is the best op­por­tu­ni­ty to in­crease much need­ed com­pe­ti­tion and choice by bring­ing low fares and great ser­vice to more cus­tomers in more mar­kets,” Jet­Blue said in a state­ment.

The rul­ing was a vic­to­ry for the Biden ad­min­is­tra­tion, which has moved ag­gres­sive­ly to block con­sol­i­da­tion in sev­er­al in­dus­tries, ar­gu­ing that it hurts con­sumers. In the air­line case, the Jus­tice De­part­ment said if Jet­Blue were al­lowed to buy Spir­it, it would es­pe­cial­ly hurt trav­el­ers who de­pend on Spir­it’s low fares.

U.S. Dis­trict Judge William Young, who presided over a non-ju­ry tri­al last year, said in the rul­ing Tues­day that the gov­ern­ment had proven that the merg­er “would sub­stan­tial­ly lessen com­pe­ti­tion” and vi­o­lat­ed a cen­tu­ry-old an­titrust law.

The New York car­ri­er ar­gued that it needs the deal to com­pete bet­ter against big­ger ri­vals that dom­i­nate the U.S. air-trav­el mar­ket.

“We con­tin­ue to be­lieve that our com­bi­na­tion is the best op­por­tu­ni­ty to in­crease much need­ed com­pe­ti­tion and choice by bring­ing low fares and great ser­vice to more cus­tomers in more mar­kets,” Jet­Blue said in a state­ment.

The rul­ing was a vic­to­ry for the Biden ad­min­is­tra­tion, which has moved ag­gres­sive­ly to block con­sol­i­da­tion in sev­er­al in­dus­tries, ar­gu­ing that it hurts con­sumers. In the air­line case, the Jus­tice De­part­ment said if Jet­Blue were al­lowed to buy Spir­it, it would es­pe­cial­ly hurt trav­el­ers who de­pend on Spir­it’s low fares.

U.S. Dis­trict Judge William Young, who presided over a non-ju­ry tri­al last year, said in the rul­ing Tues­day that the gov­ern­ment had proven that the merg­er “would sub­stan­tial­ly lessen com­pe­ti­tion” and vi­o­lat­ed a cen­tu­ry-old an­titrust law.

DAL­LAS (AP)