Berlin - Ground staff targeted German carrier Lufthansa with brief warning strikes in support of a pay demand Tuesday.

The airline warned of delays to long-haul flights and possible cancellations on domestic routes.

Services trade union Verdi said some 600 workers in catering and cargo operations had joined the limited strike at Frankfurt, Germany's main hub, early Tuesday.

Technical workers had also downed tools, Verdi, Germany's second- largest union with some 2.2 million members across the German service sector, said.

Verdi spokesman Gerhard Straube said the airports Munich, Cologne and Stuttgart had also been affected.

Verdi is demanding a pay hike of 9.8 per cent over a new 12-month contract.

Lufthansa has offered successive pay rises of 3.4 and 2.1 per cent. (dpa)