BERLIN (AP) — Pilots with Germany's Lufthansa have voted in favor of possible strike action, a union announced Sunday, saying that walkouts can still be avoided but calling the result an “unmistakable signal” to the company in a pay dispute.

The Vereinigung Cockpit union is calling for a 5.5% pay increase this year and an automatic adjustment for inflation starting next year. It has argued that Lufthansa hasn't yet made a negotiable offer in six rounds of talks.

The union said that 97.6% of pilots who took part in a ballot approved its call. It said in statement that the vote “doesn't yet necessarily lead to strike measures, but it is an unmistakable signal to Lufthansa to take the cockpit staff's needs seriously.”

The dispute comes on top of a separate altercation with a union representing Lufthansa ground staff in Germany. A one-day strike on Wednesday in that standoff led to the cancellation of over 1,000 flights.