Avianca Holdings has announced it has filed a countersuit against Kingsland Holdings as the war amongst its shareholders escalates.

In a statement, the Panama-based aviation conglomerate said a New York lawsuit filed this week seeks to halt Kingsland and its board member Roberto Kriete's "improper actions" which it says are aimed at blocking Avianca’s progress. It has also filed a motion to dismiss all of Kingsland’s claims made in a lawsuit and has also opposed its motion for an injunction to block Avianca holding any further partnership talks with United Airlines' parent, United Continental Holdings.

Kingsland Holdings is the parent firm of TACA International Airlines (San Salvador International), an El Salvador-based Central American airline that was merged with Avianca in 2010 to form AviancaTaca Holding S.A., now Avianca Holdings S.A. Kingsland now owns 21.9% of Avianca Holdings' voting shares with German Efromovich's Synergy Aerospace controlling 78%.

Earlier this month, Kingsland filed a lawsuit in a New York State Court seeking a preliminary injunction to suspend negotiations between Avianca and United. Kingsland contends that Synergy Aerospace conducted negotiations in secret and concocted a deal that benefits Efromovich personally, to the detriment of the other shareholders of Avianca.

In its statement, Avianca Holdings claims its legal papers demonstrate that it has, at all times, performed its role under the parties’ shareholder agreement, while Kingsland has explicitly breached its obligations. It also claims that Kingsland’s legal maneuvers are what it termed "a heavy-handed attempt" to obtain greater rights in the courtroom than it previously negotiated for and agreed to in the parties’ shareholder agreement.

"Avianca’s suit asks the court for an order preventing Kingsland from any further dissemination of the Company’s confidential information, requiring Kingsland to comply with the dispute resolution section of the parties’ shareholder agreement, and requiring Kingsland’s representatives to cease interfering with the shareholder agreement," Avianca Holdings said. "The Company also requested that the court dismiss Kingsland’s meritless lawsuit."

In retaliation against Kingsland's labeling of Avianca Holdings' board as a "cabal of insiders", Avianca's papers describe Kriete as a "disloyal director who has worked actively to undermine the company's strategic goals, all for his own selfish purposes."

According to Reuters, Kingsland has rejected the allegations Avianca Holdings has made asserting that it has complied with all its obligations under the shareholders' agreement.

The court is due to sit on April 6 to hear Kingsland's petition for a preliminary injunction.