Spirit Airlines rejected a $400 million merger proposal from Frontier this week, saying the offer was financially inadequate and came too late. Spirit Airlines declined an opportunity to merge with rival low-cost airline Frontier on Wednesday.

Rather than accept Frontier’s offer, Spirit said it will stick to its current plan to emerge from Chapter 11 bankruptcy.

Frontier Airlines hoped to create a low-cost airline giant, but Spirit isn’t interested—at least, not at this price. Spirit Airlines has rejected a merger offer with Frontier as it prepares to exit bankruptcy.