Berlin  - German airline Lufthansa faced further industrial action in the weeks ahead as flights slowly returned to normal Monday after a five-day strike by ground and cabin staff.

The airline, Germany's largest and Europe's second-largest, said around 130 flights would not take-off Monday, 100 of them on domestic routes, as a result of the knock-on effects from last week's strike.

"We aim to return to normal services as soon as possible," a spokeswoman said, adding, however, that this could take two weeks.

Aircraft have been grounded as they did not undergo the necessary maintenance checks during the strike from Monday to Friday last week called by the services union Verdi.

Lufthansa pilots in the Cockpit union warned they could hold a three-hour token strike this week in support for a demand for unified representation of pilots throughout Lufthansa and its two budget subsidiaries, Eurowings and Cityline.

Cockpit negotiations chief Thorsten Gommert told the Financial Times Deutschland: "Industrial action could take place at any time."

Cockpit called its members at Eurowings and Cityline out on strikes last month lasting 24 and 36 hours respectively in support of a pay demand. The dispute is still outstanding.

Last week, Lufthansa struck a pay deal with Verdi covering 21 months and providing for a phased pay rise of 7.4 per cent for 50,000 workers, as well as one-off payments. (dpa)