The German airport association ADV estimated that over 3,400 flights would be canceled due to the strike and over half a million passengers would be affected.

BERLIN, March 10 (Xinhua) -- A major warning strike at 13 German airports began on Monday, bringing much of the country's air traffic to a standstill amid two separate wage disputes involving public sector workers and aviation security personnel.

The German airport association ADV estimated that over 3,400 flights would be canceled due to the strike and over half a million passengers would be affected. German air traffic control reported that around 6,000 flight movements occur daily at German airports, with an additional 3,000 flights passing through German airspace.

Airport operators have urged passengers to avoid traveling to terminals, and Lufthansa has announced plans to revise its flight schedule to minimize disruptions.

The strike is a result of two separate wage disputes, and the trade union Verdi organized the 24-hour strike to ramp up pressure in ongoing negotiations.

The first dispute concerns public sector workers, with Verdi demanding an 8 percent wage increase or at least 350 euros (379.3 U.S. dollars) more per month, along with three additional days of leave for 2.5 million public sector employees.

Negotiations regarding these demands are currently underway between the union and German federal and local authorities, with the third round of talks scheduled for March 14. Employers have yet to present a concrete offer, which has caused "a great deal of resentment" among employees, Verdi secretary Enrico Ruemker told the German news agency dpa.

The second dispute involves aviation security personnel, who are responsible for passenger screening, cargo inspections, and other security-related tasks. Verdi is demanding improvements in occupational health and safety, 30 days of vacation, additional leave for shift work, and the ability for employees to choose their doctor during regular mandatory medical aptitude exams.

Negotiations are being held with the federal association of aviation security companies (BDLS), with the next round of talks set for March 26-27. Employers within the BDLS have criticized the warning strike, calling it "not expedient."

The warning strike in the public sector, announced on Friday, was joined on Monday by employees in the aviation security sector, as Verdi had announced on Saturday.

At the Hamburg Airport, employees advanced the strike by one day, halting work on Sunday. All flights to and from Hamburg Airport were canceled without prior notice to "ensure that the effects" of the walk-offs are felt, said a Verdi spokesperson.

Verdi said that further strikes across federal and municipal institutions are expected throughout the week.