Lufthansa has warned it might be unable to implement the €9 billion ($10 billion) financial support package agreed with the German government after the airline’s largest shareholder indicated he might vote against the package.

In a statement, Lufthansa has urged shareholders to attend an extraordinary general meeting on 25 June in a bid to shore up support for the package, which will involve Germany’s federal fund WSF taking a 20% stake in the group. Shareholders will have the final say over the package during the meeting.

Citing an interview with Heinz-Hermann Thiele in the Frankfurter Allgemeine Zeitung published on 16 June, Lufthansa says he was “critical of the conditions of the stabilisation package… and left his approval open”.

Thiele argued in the interview there was a “lack of transparency” about the deal and that Lufthansa had not revealed alternatives discussed during the talks with the government. He also disclosed in the interview that he had increased his stake in Lufthansa to over 15% and would officially inform the company of this.

Lufthansa warns: “In view of the latest public statements by the company’s largest single shareholder, Heinz-Hermann Thiele, the board considers it possible that the stabilisation package could fail to achieve the two-thirds majority of votes cast that would be required in this case.

“This would mean that Deutsche Lufthansa AG would possibly have to apply for protective shield proceedings under insolvency law a few days after the annual general meeting if no other solution is found immediately.”

A two-thirds majority will be required if the meeting’s attendance represents half or less of the share capital. Otherwise a simple majority will be sufficient.

Noting that Lufthansa’s last annual general meeting, on 5 May, had a 33% attendance, the group says it expects less than half of the share capital to be present on 25 June.

“The management board urgently appeals to all private and institutional shareholders to exercise their voting rights and to participate in the decision about the future of the company,” Lufthansa says.