Frontier Airlines CEO Barry Biffle wants to make a deal for Spirit Airlines. But, in a letter sent to the CEO of Spirit Sunday, is concerned about the lack of support from both Spirit management and its shareholders.

“We still remain very far from obtaining approval from Spirit stockholders,” Biffle said in his letter to Spirit CEO Ted Christie and General Counsel and Secretary Thomas Canfield. He noted Spirit’s decision on July 7 to delay — again — a key shareholder vote on the Frontier deal by a week to July 15. Biffle requested an additional postponement of the vote to July 27.

Frontier, and its primary shareholder private equity firm Indigo Partners, does not intend to modify its latest offer that was made on June 24, Biffle added. The cash and stock deal is valued at roughly $2.4 billion, whereas JetBlue’s all-cash offer at nearly $3.8 billion, according to a Raymond James analysis.

“We also believe that the proxy solicitation process would unquestionably benefit from the board of directors of Spirit expressly reaffirming its recommendation of the pending merger with Frontier,” Biffle said. He asked that Spirit publicly back Frontier’s offer again within 10 days, or by July 20.

(Denver International Airport)

“Our proposed combination is not only pro-competitive — making it possible to bring ultra-low fares to more routes in competition with larger, high-cost, high-fare airlines — our offer delivers significantly greater value to Spirit stockholders,” Biffle reiterated in the letter.

Frontier and Spirit unveiled plans to merge in February, but the mutually agreed to deal was disrupted by an unsolicited bid from JetBlue Airways in April. The result has been a bidding war where, despite Spirit’s repeated support for the Frontier deal, JetBlue’s greater cash offer — regardless of regulatory approval risks — has repeatedly appeared to have the support from Spirit shareholders.

Tags: frontier airlines, jetblue airways, mergers and acquisitions, spirit airlines, spirit takeover