Pilots at German airline Lufthansa will strike again this week, a labor union said on Tuesday, escalating a wage dispute that will further plague a summer of travel chaos.

It follows a strike last week that forced the cancellation of hundreds of flights.

The strike would affect pilots of both passenger and cargo divisions of the airline, said the union, Vereinigung Cockpit (VC), which groups more than 5,000 pilots.

Passenger pilots will strike on Wednesday and Thursday, and cargo pilots from Wednesday through Friday.

Last week’s strike forced the German airline to cancel about 800 flights at its main bases in Frankfurt and Munich, affecting 130,000 passengers.

Strikes and staff shortages have already forced several airlines, including Lufthansa, to cancel thousands of flights this summer, leading to long queues at major airports and frustrating people keen to start traveling again after COVID-19 lockdowns.

The VC union is demanding a 5.5% pay raise this year and automatic inflation compensation thereafter as well as better terms for entry-level pilots.

Lufthansa has said VC's demands would raise its staff costs by 40% or around 900 million euros ($899 million) over the next two years.

The airline has offered a total of 900 euros ($901.35) more in basic pay per month in two stages over an 18-month period, which it said would result in more than 18% higher pay for entry-level jobs and 5% more for senior positions.

VC's demands also come against the backdrop of soaring energy and food prices, with German inflation rising to its highest level in almost 50 years in August.