Pilots at the German flag carrier Lufthansa voted in favor of strike action by 97.6 percent on Sunday, risking severe disruptions during the lucrative summer travel season.

Strikes and staff shortages have already prompted Lufthansa and other airlines to cancel thousands of flights and create hours-long waits at major airports, aggravating vacationers eager to travel after COVID-19 lockdowns.

Marcel Groels, a pilot's union Vereinigung Cockpit (VC) board member, stated that the vote does not necessarily indicate a strike but rather that the company needs to take positive action.

"We are showing we are ready to talk," he added.

A Lufthansa representative stated that the company respects the outcome of the vote and hoped for a positive resolution at the negotiating table.

Pilots' union VC requests a 5.5% salary increase for its pilots this year and automatic inflation compensation afterward.

In addition, it desires a unified compensation structure for all employees of the Lufthansa group's airlines, which include Lufthansa and Eurowings.

On Wednesday, Lufthansa was forced to cancel more than 1,000 flights due to a protest by its ground personnel.

Separately, pilots at Lufthansa's Swiss International Air Lines (SWISS) branch rejected a contract proposal by an 80% margin, their union, Aeropers, reported on Sunday, adding that it hoped to resume negotiations with SWISS management as soon as possible.

"If management continues not to recognise the signs of the times and does not immediately offer adequate solutions, then the pilots must show the management even more clearly how dissatisfied they are," the report stated without elaboration.

Aeropers stated that the current contract terminated in April after management rejected a tentative agreement from beginning negotiations.