Frontier and Spirit Airlines will once again try to merge, only months after the Biden administration won a key antitrust court battle to block an attempt by JetBlue to buy Spirit. A combination of the two ultra-low-cost carriers would produce the country’s fifth largest airline,

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.

Embattled carrier Spirit Airlines rejected a second merger bid from rival Frontier Group on Wednesday—but the renewed efforts to reach a deal could be a sign of what’s to come for the aviation industry now that Donald Trump is back in the White House.