BERLIN — Germany’s ver.di trade union says private security personnel at the country’s Duesseldorf and Cologne-Bonn airports will stage a one-day warning strike Thursday in an ongoing dispute over wages.

Union representative Andrea Becker told the dpa news agency Wednesday that after three unsuccessful rounds of talks, ver.di hopes to put pressure on employers ahead of new negotiations scheduled to start Feb. 5.

The union is seeking pay raises of between 1.50 euros ($1.70) and 2.50 euros ($2.83) an hour for the private security workers, which has been criticized as “fully unrealistic.”