Air passengers in Germany may face delays this week due to separate actions by ground handling staff and possibly by air traffic controllers.

At 10 German airports, including major hubs Frankfurt and Munich, several thousand ground handling staff will hold meetings on Monday afternoon to discuss European Commission plans to boost competition among ground handling services at airports.

In Frankfurt alone, around 1,200 staff, or about 80 percent of ground handlers, will take part in the meetings, a regional spokesman for service trade union Verdi said on Sunday.

Germany's largest airline, Lufthansa said disruption of services, such as flight delays, was likely.

"We are actively preparing for it and hope to limit the effect on passengers as much as possible," a Lufthansa spokeswoman said.

Verdi called the meetings to inform ground handlers about EU commissioner Siim Kallas' plan to force airports to allow at least three ground handling providers to operate on their premises instead of the current two.

In addition, air traffic controllers may take action this week after their union on Friday rejected a mediator's proposal in a wage dispute.

The union's wage bargaining committee is due to meet on Monday to discuss the further course of action. The union has pledged to give 24 hours' notice of any work stoppage.

The union's chief negotiator, Dirk Vogelsang, on Sunday said that if the union did opt to strike, the strike would certainly come this week.

Air traffic controllers would stick to their plans for six-hour work stoppages if it does come to a strike, Vogelsang said.

Two strikes planned by the air traffic controllers in August, which besides Lufthansa could also have affected Air Berlin, Thomas Cook's airline Condor and TUI, were averted at the last minute.