Spirit Airlines rejected Frontier Airlines' second attempt to merge the two companies on Wednesday and will continue with its plans to exit bankruptcy. Frontier made an offer in early January for Spirit stakeholders to acquire $400 million in new debt and obtain 19% of Frontier's stock.

Frontier Airlines is making another offer to merge with bankrupt Spirit Airlines, less than two years after a previous plan fell through.

Spirit, which filed for bankruptcy protection last year, says it has rejected the new Frontier overture but would be open to a higher offer.

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.

Frontier Airlines is attempting for a second time to merge with the now bankrupt Spirit Airlines, which declared bankruptcy late last year as budget airlines struggle.

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