A 24-hour strike by the Verdi trade union grounded more than 300 planes at Germany's Duesseldorf and Cologne Bonn regional airports on Monday, as per the airport authorities.

The Duesseldorf airport announced on Monday that 205 of the planned 330 flights were canceled, 29 were diverted to other airports, and seven were rescheduled for the following day.

As of Sunday night, 131 of the 136 daily passenger flights scheduled for Cologne Bonn airport had been canceled.

Verdi declared the strike on Friday, citing the failure of collective bargaining attempts for public service workers and aviation security workers to reach an agreement.

The airports, which serve Lufthansa LHAG.DE, Turkish Airlines THYAO.IS, and Aegean Airlines AGNr.AT, were mostly vacant because customers were told of the strike in time to adjust their plans.

The union shut down air operations earlier this month with one-day strikes at seven major airports, including Frankfurt and Munich hubs, affecting over 300,000 passengers.

On Monday, public sector workers went on strike in cities around North Rhine Westphalia, most notably Cologne, Leverkusen, and Bonn.

This comes a few days after tens of thousands of passengers experienced flight delays and cancellations as staff at eight German airports went on strike for higher pay.

Germany has witnessed several strikes in recent weeks. 

Last month's strike at Berlin Brandenburg airport resulted in the cancellation or rescheduling of around 300 flights.

Postal workers, public transportation personnel, and nursery workers have also staged rallies as they cope with a rise in living costs, as a result of the Western draconian sanctions on Russia, which fired back on them.

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