Spirit Airlines (SAVEQ.US) has once again turned down a merger proposal from Frontier Group (ULCC.US), potentially signaling a wave of mergers and acquisitions in the industry.

Struggling Spirit Airlines (SAVEQ.US) on Wednesday rejected a second takeover bid from rival Frontier Group (ULCC.US), though the latter's renewed interest may signal a new wave of consolidation in the US airline industry as Trump returns to the White House.

Frontier confirmed in a statement Wednesday morning that it had submitted a takeover proposal to Spirit. Spirit later said in an 8-K filing that it had rejected the offer.

Under Frontier's proposal, Spirit shareholders would receive $400 million in Frontier debt and stock and a 19% stake in Frontier. However, Spirit said the offer was worth less to its shareholders than its bankruptcy reorganization plan and that it expects to complete the reorganization this quarter.

Frontier first proposed buying Spirit in 2022, but Jetblue Airways (JBLU.US) ultimately made a higher offer. However, in early 2024, a federal court blocked Jetblue's merger with Spirit, ruling that the deal could harm Spirit's price-sensitive customers.

Despite Spirit's latest rejection of Frontier's acquisition bid, industry insiders believe Trump's second presidential term could create a more relaxed regulatory environment for airline mergers.

Markets are currently optimistic about industry policy under Trump. Since Trump won the presidential election on November 5, 2023, the NYSE Arca Airline Index has risen 9%, while the S&P 500 has gained 6.2%.