BERLIN (Reuters) - Ground staff at German airline Lufthansa walked out at major airports on Wednesday, raising the pressure in wage talks and piling misery on travellers in Europe's biggest economy already hit by strikes on railways and public transport.

Some 100,000 passengers will be affected by the industrial action, which started at 4 a.m. (0300 GMT) and is due to run until 7:10 a.m. on Thursday, the national carrier has said.

The Verdi union has targeted the Frankfurt and Munich airports, where Lufthansa says only 10%-20% of flights will operate, as well as Berlin, Hamburg and Duesseldorf.

Verdi wants a wage rise of 12.5% for some 25,000 workers, or at least 500 euros ($537.00) more per month over a 12-month-period, plus a one-time payment of 3,000 euros to offset inflation.

A wave of nationwide industrial action in the last few weeks has hit air travel, railways and public transport, inflicting pain on the economy and fuelling discontent with German Chancellor Olaf Scholz's awkward three-way coalition.

($1 = 0.9311 euros)

(Writing by Madeline Chambers; Editing by Miranda Murray)